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Biomedical subjects

W Gaus

Publications and source records attributed to W Gaus.

At least 37 records · Page 2Linked to original sources
PubMed1999

An epidemiologic survey of human alveolar echinococcosis in southwestern Germany. Römerstein Study Group.

The inhabitants of a rural community in southwestern Germany were examined for alveolar echinococcosis (AE). The study was prompted by the recent increase of the prevalence of the parasite in foxes and the increase of fox populations: in the study area, 75% of the foxes carried Echinococcus multilocularis. The human population was screened using hepatic ultrasound and serology. All participants were interviewed for demographic and potential risk factors. Of 2,560 participants, one was identified with active AE, while 3 others had suspicious liver lesions. Another 9 participants were seropositive for specific antibodies without detectable lesions. Demographic and behavioral factors were not correlated with active or suspected cases nor with seropositivity. If the prevalence of 40/100,000 (95% confidence interval = 15-295/100,000) for active cases would be representative for the rural population in high endemicity areas, the current number of AE cases in southwestern Germany is considerably higher than previously suspected.

Adolescent↗
PubMed1998

[Comparative study of the cost-effectiveness of initial therapy with imipenem/cilastatin in secondary peritonitis].

The total costs of the hospital treatment of patients with secondary peritonitis were investigated with a prospective, randomized, multicenter study. Moreover, the cost-effectiveness of an initial therapy with Imipenem/Cilastatin was compared to selected alternative antibiotic regimens. Altogether 154 patients (77 Imipenem/Cilastatin group, 77 alternative group) that displayed Mannheim Peritonitis Scores between 16 and 26 (average 20.8) were analyzed. The average total cost of treatment was DM 11,140 per patient (range DM 2794-45,526). Patients receiving an initial therapy with Imipenem/Cilastatin incurred average costs of DM 10,455, while patients with alternative regimens caused average costs of DM 11,826. The difference between the two treatment groups was statistically significant (P = 0.037).

Adolescent↗
PubMed1998

Randomized observational studies on the economics of therapies--biometrical experience of two trials.

Economic studies in medicine are intended to investigate costs, associated with a particular problem dealing with the indication, diagnosis or therapy, for instance, whether the high costs involved in a highly intensive or innovative therapy could be balanced by the eventual savings made, due to the shorter periods of treatment. In such situations a randomized controlled trial is necessary to find out which therapy or which therapeutical strategy is least expensive in the long run. Economic studies do, however, present some specific problems. Making a list of all the cost-relevant treatment items can be very laborious, but the use of flat rates and lump sums alone cannot lead to a complete cost analysis. Often, costs between hospitals vary more than between treatment regimens. Early and sudden deaths incur low costs and may bias the results. Furthermore, costs are distributed with a long and heavy upper tail including extreme outliers. This does, in fact, complicate the estimation of the sample size. In this article, these problems are outlined and, with the help of the data obtained from two randomized economic trials in health care, solutions are proposed and discussed.

Costs and Cost Analysis↗
PubMed1997

Systemic scleroderma. Multicenter trial of 1 year of treatment with recombinant interferon gamma.

OBJECTIVE: To confirm significant improvement of the skin score in systemic sclerosis by treatment with interferon gamma in a larger group of patients and to investigate on a molecular level the influence of interferon gamma on collagen type I messenger RNA expression. DESIGN: Open, noncontrolled multicenter study. SETTING: Five outpatient clinics specializing in the care of systemic scleroderma. PATIENTS: Thirty-two patients suffering from the diffuse or limited form of systemic sclerosis and progressive disease were recruited; 20 patients finished the study. INTERVENTION: Each patient received interferon gamma, 50 micrograms subcutaneously 3 times a week for 1 year. MAIN OUTCOME MEASURE: Skin score, collagen type I messenger RNA in skin biopsy specimens. RESULTS: The patients who completed the study showed an unchanged median skin score after 1 year of therapy. In addition, similar collagen type I messenger RNA levels were detected in skin biopsy specimens taken from involved skin before and after therapy in these patients. CONCLUSIONS: Treatment of systemic scleroderma with interferon gamma is associated with stabilization of the skin score and lack of worsening of visceral involvement.

Female↗
PubMed1997

Quantitative liver function tests as surrogate markers for end-points in controlled clinical trials: a retrospective feasibility study.

Quantitative liver function tests such as the determination of galactose elimination capacity (GEC) or the aminopyrine breath test (ABT) may have the potential to serve as refined entry criteria and surrogate markers for end-points in controlled clinical trials. The magnitude of a statistically detectable difference in test results and the period of observation required to document such a difference must be known to properly design such trials. Therefore, we explored retrospectively the time course of changes in GEC and ABT and their reproducibility from a cohort of patients with alcoholic cirrhosis followed for 12 to 42 months, with a median of 34 months. In 15 patients who stopped drinking, GEC improved significantly by 0.64 mg/min/kg within 1 year (mean; 95% confidence interval [CI]: 0.42; 0.86). In contrast, it deteriorated by 0.53 mg/min/kg within 1 year (95% CI: 0.32; 0.74) in another 17 patients who continued to drink (P < .01). The residual standard deviation of the changes in GEC with respect to the patients' initial values was 0.43 mg/min/kg (95% CI: 0.32; 0.52). In addition, ABT improved significantly by 0.14% dose x kg/mmol CO2 (95% CI: 0.09; 0.18) in the abstinent group, and deteriorated by 0.09% dose x kg/mmol CO2 (95% CI: 0.06; 0.13) in the nonabstinent group (P < .01). The residual standard deviation in the above sense for ABT was 0.08% dose x kg/mmol CO2 (95% CI: 0.06; 0.10). These data indicate that clinical trials with a sample size of n = 20 in each group must achieve absolute differences (ADs) in GEC of 0.6 mg/min/kg and of 0.7 mg/min/kg to reach statistical significance at the 5% and 1% level, respectively. In the present study, a period of 11 and 12 months was necessary to observe such differences. The corresponding results for the ABT are 0.11% dose x kg/mmol CO2 (9 months of follow-up; 5% level) and 0.13% dose x kg/mmol CO2 (11 months of observation; 1% level), respectively. Provided that patients with liver diseases treated with drugs are similar to the abstinent and nonabstinent patients with alcoholic liver disease investigated in this study, such numbers could serve for the planning of controlled clinical trials, in which the control group is likely to deteriorate and the treated group is expected to improve. Trials based on GEC or ABT would require only 37 or 30 patient years of observation compared with a median of 444 patient years (range, 50-2,100 patient years) reported for various published controlled clinical trials using survival analysis.

Adult↗
PubMed1997

Double-blind, placebo-controlled study of intralesional interferon gamma for the treatment of localized scleroderma.

BACKGROUND: Localized scleroderma is characterized by circumscribed fibrotic plaques and may progress to widespread skin involvement and fibrosis. Interferon gamma (IFN-gamma) has been shown to be a potent inhibitor of collagen synthesis and of the migration and proliferation of dermal fibroblasts. OBJECTIVE: Our purpose was to determine whether IFN-gamma is effective in the treatment of localized scleroderma. METHODS: A double-blind, randomized, placebo-controlled, multicenter study was conducted. Twenty-four patients with progressive lesions received 100 micrograms of IFN-gamma or placebo subcutaneously on 5 consecutive days for 2 weeks followed by 100 micrograms of IFN-gamma or placebo once weekly for 4 weeks. Thereafter patients were observed for 18 weeks. To determine whether improvement could be related to an altered level of collagen messenger RNA (mRNA), biopsy specimens were taken from uninvolved and involved skin before and after therapy. RESULTS: The patients treated with IFN-gamma or placebo showed no significant difference in size or fibrosis of lesions or collagen type I mRNA synthesis. However, a reduction in the number of new lesions was observed in the IFN-gamma-treated group. The biopsy specimens obtained from involved skin showed a moderate increase of type I collagen and a significant decrease in the small proteoglycan decorin mRNA levels. CONCLUSIONS: The results indicate that IFN-gamma is ineffective in the treatment of localized scleroderma, but may inhibit the development of new lesions.

Collagen↗
PubMed1997

Supportive pentoxifylline in falciparum malaria: no effect on tumor necrosis factor alpha levels or clinical outcome: a prospective, randomized, placebo-controlled study.

Pentoxifylline (POF) may suppress overproduction of tumor necrosis factor alpha (TNF alpha), which is thought to contribute to complications of human falciparum malaria. However, POF is believed to improve impaired capillary blood flow, which can be impaired in falciparum malaria. To test whether POF affects TNF alpha serum levels or other variables in this disease, we administered POF (20 mg/kg/day intravenously in 150 ml of saline for five days) randomized versus placebo (150 ml of saline without POF) in addition to standard antimalarial therapy. After recruitment of 51 patients with Plasmodium falciparum malaria, those receiving POF had more nausea and abdominal discomfort than the placebo group, as expected. Eleven of 27 patients receiving POF and three of 24 patients receiving placebo requested termination of the study medication (P < 0.05). Pentoxifylline did not change the decrease of TNF alpha levels or affect the clinical course in a significant way. Since POF failed to improve the clinical situation or to impact numerous laboratory parameters (including TNF alpha, thrombin-antithrombin III, thrombomodulin, and human neutrophil elastase), the study was terminated earlier than planned. While this study does not specifically address cerebral complications of malaria, the results suggest that POF is not useful as a routine adjunct to the standard therapy of falciparum malaria.

Acetaminophen↗
PubMed1996

Quality assurance by specification and achievement of goals in palliative cancer treatment.

As the goals of palliative cancer treatments have not always been clearly specified, this paper describes how frequently the goals of palliative cancer treatment can be specified according to a given definition and how frequently those specified goals can be achieved. The clinical problems of 171 cancer patients were discussed in the Interdisciplinary Oncologic Conference (IOC) of the Cancer Centre University of Ulm (CCUU) and recommendations concerning further diagnostic treatments and/or therapy were provided. These recommendations had been documented and analysed retrospectively. The goals were classified as either cure or palliation or further investigation. If the goal was palliation, it was investigated whether or not the goal was specified as either alleviation of existing problems or prevention of impending problems. The achievement of the specified goals was assessed. Palliation was the goal of treatment in 119 (71%) of the 168 evaluable recommendations. In 83 of the 119 cases (70%), immediate treatment was recommended. The goal was specified in 57 (69%) of the 83 recommendations and could be realized in 24 of 57 specified cases (42%). Patients in this group survived longer (p < 0.01) than patients in whom the goals could not be achieved. Impending problems could be prevented more often (p = 0.001) in 14 out of 18 cases, while existing problems could be alleviated in only 10 out of 34 cases. It is concluded that specification of the goals of palliation is necessary because it is impossible to decide if a goal of treatment could be achieved or not unless the goal of treatment has been defined (as existing/impending problem). The prevention of impending problems could be investigated in prospectively controlled clinical trials.

Adult↗
PubMed1996

[Comparative study of the cost-/effectiveness relationship of initial therapy with imipenem/cilastatin in nosocomial pneumonia. Group study].

AIM OF THE STUDY: The present study assessed the total cost involved in the therapy of nosocomial pneumonia. Cost for patients receiving Imipenem as initial antibiotic therapy was compared with that for patients treated by selected alternative regimens. Secondary objectives included the evaluation of fever days, days of antibiotic therapy, days at ICU and days of overall hospitalisation required for the treatment of the nosocomial pneumonia for both methods of treatment. METHODS: A prospective randomised open study involving multiple study sites was conducted. Total cost, efficacy and safety of an initial therapy with Imipenem were compared to results achieved with selected other antibiotic regimens. Altogether 109 patients were enrolled into the study; 85 patients could be assessed. RESULTS: Both treatment methods showed equal clinical efficacy. Total cost of the therapy of nosocomial pneumonia for all patients was in the range between 1,616 DM and 82,141 DM, the arithmetic mean was calculated to be 11,307 DM and the median was found to be 6,507 DM. Imipenem-treated patients incurred lower cost (median 5,649 DM, mean 10,009 DM) than patients treated with other antibiotics (median 9,334 DM, mean 12,701 DM). CONCLUSION: The total cost of treatment of nosocomial pneumonia was lower for Imipenem-treated patients than for patients receiving initially other selected antibiotic regimens. The savings are apparently due to a faster recovery of the patients resulting in reduced duration of therapy. The study shows that assessment of cost of therapy per day might be misleading in the economic analysis of antimicrobial chemotherapy.

Adolescent↗
PubMed1995

Studies on the efficacy of unconventional therapies. Problems and designs.

Many unconventional therapies (e.g. dietary, phytotherapy, acupuncture, homeopathy) are well known and often applied, but their efficacy has hardly been proven. New trial designs and study components must be found to meet the specific demands of the particular unconventional therapy on one hand and keep the high methodological standard of controlled clinical trials on the other hand. Biometricians and unconventional therapists are challenged to develop such designs. Typical problems in designing studies of unconventional therapies include that placebo is not possible, therapies cannot be masked, outcome variables are not reliable, therapy is highly individualized, and studies on the efficacy of soft therapies require many patients and long treatment periods. Studies with unconventional therapies should be performed by practitioners (because they use these therapies), but this leads to further problems. Some solutions are given in examples: A study is described investigating the herbal remedy Kava-Kava for patients in the state of anxiety, tension and restlessness; a study on classical homeopathy for chronical headaches is specified; some designs for dietary studies in patients with rheumatoid arthritis are compared. A design called "cross-allocation of patients to two treatments with randomization option" and the "N-of-1 design", also called "single case design" are described and discussed. The "change-to-open-label design" could be useful to investigate soft and natural therapies which require studies with many patients and long-term treatment.

Arthritis, Rheumatoid↗
PubMed1994

An international randomized study with long-term follow-up of single versus combination chemotherapy of multibacillary leprosy.

A total of 307 patients with lepromatous leprosy and borderline lepromatous leprosy were randomized to dapsone monotherapy or to one of two types of drug combinations. A 3-year treatment phase was followed by a 5-year observation phase. The evaluation included 233 patients for whom together there were 1,404 years of observation. A total of 1,956 blinded histopathological specimens were processed centrally. When entering the trial isolates from 13 patients (5.6%) showed dapsone resistance in the mouse footpad test, and these patients were evaluated separately. Dapsone monotherapy (68 patients) had the same frequency of cure as the combination of dapsone and rifampin (77 patients) or the four-drug regimen consisting of dapsone, rifampin, isoniazid, and prothionamide (75 patients). We did not find a significant difference in the clearance of bacteria either between the monotherapy and the two-drug combination or the monotherapy and the four-drug combination. Six months after the initiation of treatment, disease in 15% of the patients who received dapsone monotherapy but none of the patients who received combined treatment were clinically progressive. After another 1 to 9 months of treatment the disease in all patients was stable or regressive. There was no difference in the type or frequency of reactions. Only after the end of the scheduled observation phase three relapses were reported. All three treatment regimens well tolerated. Dapsone monotherapy is highly effective in the treatment of multibacillary leprosy under the conditions of well-controlled treatment. Combination regimens seem only to accelerate the regression of the active disease when they are compared with monotherapy with dapsone. The mouse footpad test does not reflect the clinical resistance and cannot be recommended for use in making therapeutic decisions.

Adolescent↗
PubMed1994

Change-to-Open-Label Design. Proposal and discussion of a new design for clinical parallel-group double-masked trials.

The "Change-to-Open-Label Design" (COLA-design) is proposed to overcome some of the ethical and organizational problems of the usual double-masked design in certain situations while preserving its scientific rigor. Patients are randomized on a doubled-masked basis into treatment groups. During the trial the patient or the treating physician may ask for a change from the masked treatment to any open-label treatment of their choice (experimental or not), if the masked treatment is thought to be unsatisfactory. It seems to be easier to obtain a patient's informed consent to participate in placebo controlled double-masked trials especially for long term studies. The main outcome variable in COLA-design is the time until a patient demands for such a change. "Survival analysis" is a powerful statistical method to evaluate this outcome variable. Even patients lost from observation can be included in the evaluation: they still deliver censored outcome values. Evidently, in trials with a COLA-design the patient's personal impression of the therapy is the most important factor in its assessment. Therapeutical success is mingled with undesirable effects into the outcome measure; therefore this design is especially applicable to investigate treatments supposed to increase quality of life.

Double-Blind Method↗
PubMed1993

Gabexate mesilate in human acute pancreatitis. German Pancreatitis Study Group.

BACKGROUND: A multicenter controlled study was performed to evaluate the effect of high doses of the low molecular weight protease inhibitor gabexate mesilate on mortality and complications associated with moderate and severe acute pancreatitis. METHODS: Two hundred twenty-three patients from 29 hospitals were entered in the randomized, double-blind trial. Admission to the study was based on strict criteria excluding mild acute pancreatitis. The patients received placebo or 4 g gabexate mesilate per day intravenously for 7 days. All patients were followed up for 90 days after randomization. The analysis was based on 14 complications, including death. RESULTS: There was no statistical difference in either mortality or complications associated with acute pancreatitis between the placebo and gabexate mesilate groups. CONCLUSIONS: The results show that gabexate mesilate was not effective in preventing complications and mortality in acute pancreatitis.

Acute Disease↗
PubMed1993

Once-daily versus thrice-daily dosing of netilmicin in combination with beta-lactam antibiotics as empirical therapy for febrile neutropenic patients.

In a prospective, randomized trial, netilmicin given once daily (OD) was compared in terms of efficacy and safety with the conventional 8-hourly dosing regimen (TD), both in combination with a broad spectrum beta-lactam, as initial empirical therapy for febrile neutropenic patients; the total daily dosage of netilmicin in each group was 6 mg/kg body weight. Twenty-nine of the 116 (25%) evaluable patients had microbiologically documented septicaemia, most of which were caused by Gram-positive bacteria, 41 (35%) had microbiologically documented infection without bacteraemia and 46 (40%) had possible infection. Highest peak serum concentrations of netilmicin in the OD group were significantly higher and trough serum concentrations significantly lower than in the TD group. A multivariate analysis revealed that neither the dosage regimen nor the peak serum concentration of netilmicin were determinants of a favourable outcome. The response rates of both groups to the initial treatment regimens were comparable and increased similarly following modification of the initial therapy. Response rates were particularly poor in patients with lower respiratory tract infection and in those who remained neutropenic throughout the course of treatment. The incidence of nephrotoxicity was low and did not differ significantly between groups. Once-daily dosing of netilmicin appears to be as effective and as safe as thrice-daily dosing, but is unlikely to further improve the response of febrile neutropenic patients to empirical therapy.

Anemia, Aplastic↗
PubMed1992

Structured reporting of medical findings: evaluation of a system in gastroenterology.

A system using structured reporting of findings was developed for the preparation of medical reports and for clinical documentation purposes in upper abdominal sonography, and evaluated in the course of routine use. The evaluation focussed on the following parameters: completeness and correctness of the entered data, the proportion of free text, the validity and objectivity of the documentation, user acceptance, and time required. The completeness in the case of two clinically relevant parameters could be compared with an already existing database containing freely dictated reports. The results confirmed the hypothesis that, for the description of results of a technical examination, structured data reporting is a viable alternative to free-text dictation. For the application evaluated, there is even evidence of the superiority of a structured approach. The system can be put to use in related areas of application.

Attitude to Computers↗
PubMed1992

Recommendations of the German Association for Medical Informatics, Biometry and Epidemiology for education and training in medical informatics.

In the fields of health care and medicine there is an immense demand for a systematic application of methods of information processing and for the use of computers. Obviously, to that end well-trained scientists and qualified personnel must be available. With the present recommendations on education and training in medical informatics the German Association for Medical Informatics, Biometry and Epidemiology (GMDS) proposes structure and contents of medical informatics curricula and courses. The recommendations describe a 2-dimensional educational framework with different education levels in one dimension and various types of educational needs and orientation in the other one. The recommendations comprise at the university level education as well specialized curricula covering the total spectrum of medical informatics as well as informatics curricula with medical informatics as integrated applied subject or subsidiary subject, respectively. Besides these informatics-oriented approaches medical-oriented programs of education in medical informatics are recommended, e.g., post-graduate education in medical informatics for physicians based on foundations in medical informatics as part of their initial training in medicine. At the level of polytechnical schools curricula of medical documentation and informatics and at the level of professional schools training in medical documentation are recommended. This report is a translation of its German original. Although considered by the GMDS as recommendations for the Federal Republic of Germany, the text may also contribute to the development of an international, especially European framework of training in medical informatics.

Germany↗