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R Rau

Publications and source records attributed to R Rau.

At least 37 records · Page 2Linked to original sources
PubMed2002

Uniform decrease of alpha-global field power induced by intermittent photic stimulation of healthy subjects.

Nineteen-channel EEGs were recorded from the scalp surface of 30 healthy subjects (16 males and 14 females, mean age: 34 years, SD: 11.7 years) at rest and under trains of intermittent photic stimulation (IPS) at rates of 5, 10 and 20 Hz. Digitalized data were submitted to spectral analysis with fast fourier transformation providing the basis for the computation of global field power (GFP). For quantification, GFP values in the frequency ranges of 5, 10 and 20 Hz at rest were divided by the corresponding data obtained under IPS. All subjects showed a photic driving effect at each rate of stimulation. GFP data were normally distributed, whereas ratios from photic driving effect data showed no uniform behavior due to high interindividual variability. Suppression of alpha-power after IPS with 10 Hz was observed in about 70% of the volunteers. In contrast, ratios of alpha-power were unequivocal in all subjects: IPS at 20 Hz always led to a suppression of alpha-power. Dividing alpha-GFP with 20-Hz IPS by alpha-GFP at rest (R = alpha-GFP(IPS)/alpha-GFP(rest)) thus resulted in ratios lower than 1. We conclude that ratios from GFP data with 20-Hz IPS may provide a suitable paradigm for further investigations.

Adult↗
PubMed2001

[Use of glucocorticoids in rheumatoid arthritis. Inhibition of disease progression versus risk of steroid osteoporosis].

This is a short overview of low dose oral treatment with 5-7.5 mg prednisolone/day in RA with emphasis on radiographic progression. Short-term studies over 1-2 weeks with 7.5-15 mg prednisolone/day demonstrate advantage over placebo and--less so--over NSAID in improving RA symptoms; over 6-12 months prednisolone seems to be less superior. Older studies were unable to demonstrate an inhibition of progression seen on radiographs. In the Kirwan study, there was a significant inhibition of x-ray progression with 7.5 mg prednisolone/day versus placebo. The German low-dose prednisolone treatment (LDPT) study demonstrated a significant retardation of radiographic progression with only 5 mg prednisolone/day in addition to DMARD treatment with parenteral gold or methotrexate versus DMARD + placebo in early RA during the first year of treatment while there was no difference between both groups during the second year. These data are in favor of a "bridging" treatment with low dose prednisolone. The risks of corticosteroid treatment are discussed, including an increased mortality rate as an independent risk factor. Two randomized studies and a metaanalysis indicate the development of steroid osteoporosis in RA already with low doses. As with every treatment, benefit and risk have to be considered carefully.

Arthritis, Rheumatoid↗
PubMed2001

A method to score radiographic change in psoriatic arthritis.

INTRODUCTION: Radiographic features of psoriatic arthritis (PsA) are very characteristic and differ from those observed in rheumatoid arthritis, especially in two aspects: 1) the distribution of affected joints (i.e. DIP joints), 2) the presence of destructive changes and bone proliferation at the same time. A scoring method for PsA, therefore, has to account for these characteristics of PsA. OBJECTIVE: To develop, describe and validate a method for scoring radiographic changes in patients with PsA. DESCRIPTION OF THE METHOD: Forty joints of the hands and feet are scored for destruction and proliferation. In the destruction score (DS) grading on a 0-5 scale is based on the amount of joint surface destruction: 0 = normal, 1 = one or more erosions with an interruption of the cortical plate of > 1 mm with destruction of the total joint surface up to 10%, 2 = 11-25%, 3 = 26-50%, 4 = 51-75%, 5 = > 75% joint surface destruction. The proliferation score (PS) sums up any kind of bony proliferation typical for PsA; graded 0-4: 0 = normal, 1 = bony proliferation of 1-2 mm or bone growth < 25% of the original size (diameter), 2 = bony proliferation 2-3 mm or bone growth 25-50%, 3 = bony proliferation > 3 mm or bone growth > 50%, 4 = bony ankylosis. The DS (0-200) and the PS (0-160) can be summed up to the total score (0-360). VALIDATION OF THE METHOD: To validate the method x-rays of 20 patients with active PsA taken 3 years apart were read twice in pairs, knowing the chronological order but not knowing demographic, clinical or laboratory data of the patients. The data were analyzed with a hierarchical analysis of variance model. RESULTS: There was good agreement between the first and the second reading of the same rater and between the two raters regarding the destruction score. The agreement regarding the proliferation score was lower but still acceptable. The reliability of the method to describe change over time--relation of progression (intra-patient variance) to the measurement error (inter-rater variance)--was 3.9 for the DS, 2.8 for the PS and 4.1 for the total score. The minimal detectable change when the readings of two raters were compared (inter-rater MDC) was 5.8, 5.0 and 4.6%, respectively of the maximum possible score for the destruction, the proliferation and the total score. These data compare very well with the results of standard scoring methods in rheumatoid arthritis. CONCLUSION: We propose a method for scoring radiographic change in psoriatic arthritis which reliably quantifies the progression of the disease seen on radiographs.

Adolescent↗
PubMed2001

Slowing of disease progression in rheumatoid arthritis patients during long-term treatment with leflunomide or sulfasalazine.

Radiographic disease progression with leflunomide and sulfasalazine treatment was assessed in rheumatoid arthritis patients in a double-blind trial that was placebo controlled for the first 6 months. Completers at 6 months opted to continue on 12- and 24-month double-blind extensions; patients in the placebo group were switched to sulfasalazine. Changes in Larsen scores were assessed in evaluable patient cohorts at 6 (n=228), 12 (n=136), and 24 (n=65) months. Changes in Larsen scores and erosive joint counts with leflunomide and sulfasalazine at 6 months showed significantly less radiographic progression than placebo. Sustained retardation of radiographic progression was seen in the 24-month intent-to-treat cohorts (delta Larsen scores: leflunomide -0.07, sulfasalazine -0.03). Changes in erosive joint counts within the 24-month leflunomide cohort suggest halting of disease progression for patients who continued in the study for 2 years (leflunomide -0.92, sulfasalazine 0.80). Leflunomide was well tolerated with no unexpected adverse events during the 2-year period. This study demonstrates that slowing of disease progression with leflunomide, observed as early as 6 months, is maintained long term in patients who complete 2 years of treatment.

Adult↗
PubMed2001

Intermittent 20-HZ-photic stimulation leads to a uniform reduction of alpha-global field power in healthy volunteers.

19-channel-EEGs were recorded from scalp surface of 30 healthy subjects (16m, 14f, mean age: 34 ys, SD: 11.7 ys) at rest and under IPS (Intermittent Photic Stimulation) at rates of 5, 10 and 20 Hertz (Hz). Digitalized data underwent spectral analysis with fast fourier transfomation (FFT) yielding the basis for the computation of global field power (GFP). For quantification GFP values in the frequency ranges of 5, 10 and 20 Hz at rest were divided by the corresponding data gained under IPS. While ratios from PDE data showed no stable parameter due to high interindividual variability, ratios of alpha-power turned out to be uniform in all subjects: IPS at 20 Hz always led to a suppression of alpha-power. Dividing alpha-GFP at rest by alpha-GFP under 20-Hz IPS thus resulted in a ratio < 1. We conclude that ratios from GFP data are a stable diagnostic paradigma.

Adult↗
PubMed2001

Psychosocial work characteristics and perceived control in relation to cardiovascular rewind at night.

This study examined the effects of psychosocial work characteristics on cardiovascular rewind at night. Ambulatory 24-hr recordings of blood pressure (BP) and heart rate (HR) of 75 borderline hypertensive and 74 normotensive men were related to diary ratings of perceived control (PC) and to scores of psychological demand (P), control (C), and social support (S) at work determined by an occupational classification system. Multiplicative interaction terms for job strain (P x C), isostrain (P x C x S), and Job Strain x Perceived Control (P x C x PC) were calculated. The P x C x PC interaction predicted diastolic BP at night but not at work. A delayed latency to attain the lowest systolic BP during the night was found for jobs with high job strain and isostrain. Low perceived control and social support were associated with higher HR at work and at night. A logistic regression analysis indicated that the interaction between P x C x PC and the body mass index was independently associated with borderline hypertension.

Adult↗
PubMed2001

Identification of radiologic healing phenomena in patients with rheumatoid arthritis.

OBJECTIVE: Conventional radiographic scoring methods in rheumatoid arthritis (RA) are designed to quantify progression and disregard any improvement. Reparative changes observed during longterm followup of RA have rarely been described as healing phenomena. Healing may become increasingly important with the availability of more potent antirheumatic drugs. We investigated whether radiologic healing phenomena can be identified by different observers in a blinded fashion. METHODS: Healing phenomena were defined as (1) reappearance (and sclerosis) of the cortical plate, (2) partial or complete filling in of an erosion, or (3) subchondral bone sclerosis with osteophyte formation (secondary osteoarthritis). Pairs of radiographs of hands, wrists, and forefeet [taken 2 to 8 (mean 4.8) yrs apart] of 34 patients were selected from longterm studies: 24 sets with healing phenomena and 10 with progressive disease without healing. The radiographs were blinded and read in pairs in random order by 3 observers unaware of the patients selected for the study. One observer read the set a second time after 8 weeks, resulting in a total of 4 observations. Thirty-eight joints were rated 0 to 5 depending on the amount of surface destruction. In addition an attempt was made to identify joints with healing phenomena. The data were analyzed with help of descriptive statistics such as means, standard deviations, and frequency tables. RESULTS: Out of 1292 joints scored at the second time point, 74 had healing phenomena. These joints were identified in a mean of 89% (95/89/88/82%, respectively) in the 4 observations performed by the 3 readers. Patients without healing phenomena were correctly identified by all observers. In 54 joints less typical healing phenomena were seen in all observations. Sixty-two joints with healing in addition to the 74 joints were seen in 3 observations, 76 in 2, and 127 in one observation. All observers agreed that 1090 joints had no healing phenomenon. The 24 patients with healing had a slight reduction in the Ratingen score, while the 10 patients without healing showed a moderate progression. In the group with healing an increase and decrease in the score occurred in the same patients at different joints. CONCLUSION: In patients with RA followed for several years healing or reparative changes of erosions can be observed. These phenomena can be identified by different observers with high sensitivity even when the observers are blinded to chronological sequence of the films.

Arthritis, Rheumatoid↗
PubMed2000

Response to methotrexate treatment is associated with reduced mortality in patients with severe rheumatoid arthritis.

OBJECTIVE: This study investigated whether efficacious methotrexate (MTX) treatment has an impact on mortality of patients with severe rheumatoid arthritis (RA). METHODS: In this prospective, observational, one-center study, patients with severe RA refractory to other disease-modifying antirheumatic drugs started MTX treatment between 1980 and 1987. Patients were divided into 4 different groups according to their response to MTX treatment after 1 year (>50% improvement [n = 99], 20-50% improvement [n = 70], no improvement [n = 52], and discontinued treatment [n = 35]). After a followup of 7.5-15.3 years (mean 10 years), the numbers of deaths were assessed in the different groups. Standardized mortality ratios (SMR) were calculated by comparing the number of observed deaths in the study with the number of expected deaths in an age- and sex-matched sample of the general population. RESULTS: Two hundred seventy-one patients entered the study between 1980 and 1987. In 1995/1996, outcomes for 256 patients (94.5%) could be documented; 88 patients (34.4%) had died. In patients with >50% improvement after 1 year, the SMR was 1.47, while in patients with 20-50% improvement, the SMR was 1.85. In both groups combined, the SMR was 1.64 (95% confidence interval [95% CI] 1.11-2.17), compared with 4.11 (95% CI 2.56-5.66) in patients without improvement. Patients who had discontinued MTX treatment during the first year had an SMR of 5.56 (95% CI 3.29-7.83). CONCLUSION: Patients with severe RA who do not respond to MTX treatment have a poor prognosis, with >4-fold increased mortality compared with the general population, while RA patients who respond to MTX treatment have only a moderately increased mortality rate.

Antirheumatic Agents↗
PubMed2000

[Concept for nationwide cooperation in planning and implementing multicenter studies].

In Germany, good clinical multicenter studies that are not supported by pharmaceutical companies are rarely performed. Good supranational industry-sponsored studies are usually aimed at the registration of new (expensive) drugs. The preconditions for co-operation in conducting industry-independent studies which are of interest for the scientific community have been improved substantially in Germany by instituting the working group of co-operating arthritis centers, the so-called core documentation where 32,000 patients with rheumatic conditions were documented in 1997 and the institution of a sophisticated information system ("RheumaNet"). The executive board of the German Rheumatology Association has set up an "ad hoc commission" that agreed to institute a "Committee for the Coordination of Clinical Studies in Rheumatic Diseases". In this committee rheumatologists subspecialized from medicine, orthopedic, pediatrics working in universities, hospitals and private practice as well as specialists in statistics and epidemiology shall be represented. In principle this committee is independent of the co-operating arthritis centers and the RheumaNet. All members of the German Rheumatology Association are invited to cooperate with this committee by contributing to the clinically important questions and participating in clinical studies. The committee has to define key questions in rheumatology and shall plan and organize multicenter studies to answer these questions. In addition, study protocols of pharmaceutical companies may be examined as to their importance, quality, and feasibility.

Antirheumatic Agents↗
PubMed2000

Low dose prednisolone therapy (LDPT) retards radiographically detectable destruction in early rheumatoid arthritis--preliminary results of a multicenter, randomized, parallel, double blind study.

OBJECTIVE: To test if continuous LDPT decreases radiographically detectable joint destruction in early RA. METHODS: Patients with active RA (< 2 years from symptom onset) were treated with prednisolone 5 mg daily or placebo for 2 years in a double blind, randomized, multi-center study. At the same time in all patients DMARD treatment with either gold sodium thiomalate (GSTM) or methotrexate (MTX) was started; in the case of side effects or inefficacy the medication could be switched to the other DMARD. Radiographs of hands and forefeet were taken at baseline and after 6, 12 and 24 months. All radiographs were evaluated by one observer (S.W.) knowing the time sequence of the film but unaware of the patient identity or treatment using the Ratingen score and van der Heijde's modification of Sharp's method. RESULTS: 196 patients were included; 76 patients completed the study per protocol. Of these patients 34 were treated with prednisolone, 42 with placebo, 48 initially with GSTM, 28 with MTX. 17 patients switched from GSTM to MTX, 1 from MTX to GSTM. The mean values of the radiographic scores of both groups are given in the table. During the first year, especially during the first 6 months, the radiographic progression within the prednisolone group was significantly lower than in the placebo group: the Sharp erosion score increased by 0.4% of the maximum possible score during the first and the second 6 months in the prednisolone group, while in the placebo group there was an increase of 1.8% during the first 6 months and 0.8% during the second 6 months. During the second year the progression was significantly lower (-0.1% in the prednisolone group, 0.2% in the placebo group). After 24 months the total score had increased by 2.6% of the maximum score in the placebo group and by 1.1% in the prednisolone group. The results of the completers were confirmed by the intention-to-treat analysis (80 patients in the prednisolone group, 86 patients in the placebo group). CONCLUSION: Continuous low dose prednisolone treatment with 5 mg daily over 2 years administered in addition to conventional DMARD treatment with MTX or GSTM decreases radiographic progression in early RA. The results of the study also show that in the placebo group there is a sharp decrease of the progression after 6-12 months as a result of the DMARD treatment. During the second year there is nearly no progression in this group. The data of the "completers" are confirmed by the analysis of the "intention to treat" population.

Adult↗