An insight into cortisol and polymyositis control with steroid therapy

In the present report we have developed a mathematical model to describe th e processes involved during high steroid therapy. We have shown that the mo del can predict clinical observations as well as determine the optimum ster oid regimen without relying on trial and error methods. The model incorpora tes rate processes that simplify the physiological complexity as a few repr esentative steps. In this way, it is possible to simulate clinical observat ions and then to predict clinical outcomes due to drug concentrations or ad ditional reactions within the body. Specific examples are provided from pat ients with polymyositis and Backer's disease. For the first time, we provid e an explanation into the control of cortisol production, and determine an optimum prednisolone concentration in order to minimize steroid side effect s while maintaining adequate control of muscle degradation. (C) 2001 Harcou rt Publishers Ltd.