Background: Systemic sclerosis (SSc) is an autoimmune disease associated with significant mortality and morbidity. Cardiovascular causes are the single largest contributor to premature death. To date, much of the focus on managing the care of SSc patients has concentrated on traditional risk factors related to fibrotic and microvascular dysfunction. There is, however, evidence of a strong cardiovascular component to the disease and points to macrovascular dysfunction as being a key contributor to the premature mortality associated with SSc. This thesis reports on the conduct of a multi-centre, randomised, placebo-controlled clinical trial (the SSTEP Study). The aim of the study was to assess whether oral Iloprost was more effective than placebo in reducing cardiovascular events and disease progression in SSc. Methods: Two hundred and sixteen patients with systemic sclerosis were recruited, between February 2002 and February 2005, at nine centres in the UK and Ireland. After one month placebo run-in, participants were randomised to either oral Iloprost (50-200mcg daily) or matched placebo. Baseline demographics, disease characteristics and organ screening data were collected, and participants were reviewed annually for endpoint measurements; CV events, SSc disease progression and mortality, with regular safety reviews between these annual visits. Participants were followed up for a period of 4 to 7 years. Results: Data analysis of the combination of the two measures (survival free from death or a cardiovascular event) demonstrated a trend towards favouring Iloprost over placebo but the difference was not statistically significant (Logrank test: Chi square=0.75, p=0.39). When time to a confirmed cardiovascular endpoint alone was examined there was a suggestion of a benefit from Iloprost, but the difference was again not statistically significant (Logrank test, Chi square =0.82, p=0.37). There was no statistically significant change in the rate at which organ screening endpoints occurred throughout follow-up, and for each endpoint there was no statistically significant difference between results in patients randomised to Iloprost compared to those randomised to placebo. Withdrawal from the treatment to which the patient was randomised was frequent with 97 (45%) of the total participants discontinuing study medication. ‘On treatment’ analysis, undertaken using the endpoint of death or confirmed cardiovascular endpoint, just failed to show statistical significance at the 5% level (p=0.054). Conclusion: The results of the SSTEP study showed that there was a trend towards favouring oral Iloprost over placebo in systemic sclerosis, though there was no statistically significant evidence to recommend its use to prevent disease progression. The high rate of withdrawal from both Iloprost and placebo hindered the possibility of demonstrating that Iloprost was effective in this study. It cannot be concluded that it is a useful therapy that may prevent premature mortality or progression to cardiovascular disease in this patient group.

Techn. Hochsch., Diss., 2005--Aachen.

No description available.

名古屋大学博士学位論文 学位の種類 : 博士(医学)(論文) 学位授与年月日:平成5年9月14日 家田信人氏の博士論文として提出された

Die Störung der intestinalen Mikrozirkulation gilt als ein kardinaler Mechanismus für die Entwicklung des Multiorganversagens bei Sepsis. Da das Intestinum für mikrozirkulatorische Studien klinisch kaum zugänglich ist, wurden die Auswirkungen einer Therapie mit den antioxidativen Substanzen Oxypurinol und U-74389G (Lazaroid) bzw. den vasoaktiven Substanzen Iloprost (Prostacyclin-Analogon) und Dopexamin auf die intestinale Mikrozirkulation und die systemische Mediatorfreisetzung in einem Tiermodell mit moderater und hoher Endotoxin-Belastung untersucht. Die intravitalmikroskopische Untersuchung der Kapillarperfusion in der Muskularisschicht bei Endotoxinämie erbrachte eine Verbesserung durch Oxypurinol- und Dopexamingabe. Die Perfusion der Mukosa konnte vor allem durch eine Iloprostapplikation gesteigert werden. Die Endotoxin-induzierte, intestinale Leukozytenadhärenz wurde insbesondere durch die Behandlung mit den antioxidativen Substanzen vermindert. Beide therapeutischen Optionen bewirkten eine ca. 60 %ige Reduktion der initialen Tumornekrosefaktor-alpha-Freisetzung in der Versuchsreihe mit der niedrigeren Endotoxin-Dosis. Parallel dazu konnte anhand von Malondialdehyd-Analysen gezeigt werden, dass Oxypurinol und U-74389G wirksam die intestinale, Radikal-induzierte Lipidperoxidation verringerten. Der intestinale mikrovaskuläre Blutfluss konnte durch beide vasoaktiven Substanzen - sowohl bei moderater als auch bei erhöhter Endotoxin-Dosierung - signifikant gesteigert werden. Die Ergebnisse beider Teilstudien bestätigten, dass sowohl reaktive Sauerstoffspezies als auch eine inadäquate Perfusion in der Mikrozirkulation wesentliche pathogenetische Faktoren bei Endotoxinämie bzw. Sepsis darstellen und entsprechende Therapieformen indiziert und effektiv sind. Eine kombinierte Gabe beider Substanzklassen erscheint daher sinnvoll und sollte in weiteren tierexperimentellen und klinischen Studien evaluiert werden. / The disturbance of the intestinal microcirculation is regarded as a pivotal mechanism in the development of multiorgan failure related to sepsis. Since the intestine is clinically not accessible for microcirculatory studies, the effects of a therapy with the antioxidants oxypurinol and U-74389G (lazaroid) as well as the vasoactive substances iloprost (a prostacyclin analogue) and dopexamine on the intestinal microcirculation and the systemic mediator release was studied in an animal model with moderate and high endotoxin challenge. The intravital microscopic examination of the capillary perfusion in the muscularis layer of the intestine during endotoxemia revealed an improvement by administration of oxypurinol and dopexamine. The perfusion of the mucosa could be increased by iloprost administration. The amount of the endotoxin induced, intestinal leukocyte adherence was especially decreased by the treatment with the antioxidants. Both therapeutic options caused a 60 % reduction in the initial tumor necrosis factor-alpha-release in the experiments with the lower endotoxin dose. Malondialdehyde analyses showed that oxypurinol and U-74389G reduced effectively the intestinal, radical-induced lipid peroxidation. The intestinal microvascular blood flow could be significantly increased by both vasoactive substances - as well as with moderately than also with elevated endotoxin-dosage. The results of the study confirmed that both reactive oxygen-species as well as an inadequate perfusion in the microcirculation represent essential pathogenetic factors during endotoxemia as well as sepsis and index corresponding therapy-forms and participates effective. A combined offering both substance-classes appears therefore meaningfully and should be evaluated in further experimental and clinical studies.