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Aims: Controlled clinical trials collect huge amounts of high quality data. It is a waste of information to evaluate these data only for the efficacy and safety of the investigational medication. We propose extended evaluations of large trials for scientific purposes, especially to find the most important risk factors of the disease or variables which are associated with risk to have the disease.
Methodology: The SPICE study is a controlled, randomised, completely masked trial that has investigated the efficacy of the Crataegus product WS 1442 in 2681 randomised patients with congestive heart failure (CHF). It was initiated and sponsored by Dr. Willmar Schwabe Pharmaceuticals. Results have already been published. We asked the sponsor to send us the data for an extended evaluation which was performed with a multivariate Cox regression model to find risk factors for the composite endpoint cardiac death, non-fatal myocardial infarction or hospitalisation due to progressive heart failure.
Results: Most important risk factors are lower New York Heart Association (NYHA) function class, younger age and higher left ventricular ejection fraction. Patients had less cardiac events when taking glycosides, antiarrhythmics, nitrates, diuretics, beta blockers and calcium antagonists, so patients with a high number of cardiovascular medication have a poorer prognosis. Three scenarios for the interpretation of cardioactive medications as “risk” are presented. We assume that symptoms leading to the indication of a specific cardioactive medication are the risk. This risk is only partly balanced by medication intake. In general, the intake of cardioactive medication is associated with the risk to have the disease.
Conclusion: An extended evaluation of large clinical studies finds out what is important for the outcome besides specific efficacy of the investigational drug. This is usually not the scope of pharmaceutical companies, but useful for science, doctors and patients.