Systems science applications in medicine are known since the 1950s when Ludwig von Bertalanffy was founding his general theory of living systems. At present, by new technological and formal methods in modern biology and medicine this perspective gets new support.

The emerging field of Systems Medicine aims at a systemic understanding of health and disease on the basis of complex molecular data sets that are obtained by high-throughput technologies and that are analyzed by mathematical tools of complexity research. These new approaches promise better diagnosis, treatments, predictions and preventions of diseases by personalized data and participation of the patient.

But not only systems thinking in medicine, also systems thinking of medicine is important: Beyond economic approaches the methodologies of systems analysis and systems design are useful tools for the structural and functional analysis as well as the transformation of health care systems.

Systems Medicine

Maintenance of health and the development of diseases are the result of complex dynamic interactions. Systems Medicine is the application of systems biology approaches to medical research and medical practice. Its objective is to integrate a variety of biological/medical data at all relevant levels of organization using the power of computational and mathematical modelling, from the level of inter- and intracellular molecular networks of the cell to the levels of the interdependence of humans and their environments.

As many side-effects of medications are caused by the linkage of different organ systems such as heart and lung, the immune system, endocrine system and nervous system, a new approach in medicine is necessary. These connections are statistically known as co-morbidity.

The first step towards systems medicine intended a better understanding of functions and dysfunctions of the organism by using computer simulations of cell and tissue processes. The connections can now be interpreted by such models that are based on data from inter- and intracellular molecular networks (cytokines, neurotransmitters, etc.).

Health Care Systems

At present, also clinical systems medicine is constituted that focusses on the interaction of organismic subsystems. Some protagonists call this the 4P medicine, for personalized (individual genome analysis), predictive, preventive and participative medicine (L. Hood, Institute for Systems Biology, Seattle) to develop innovative therapies and tailored preventive treatments.

The future outlook is a scenario in which the health care system itself might change based on these findings. A complementary research focus of the Bertalanffy Center in Service Systems Design for large scale, multi-stakeholder complex social systems like health care might be the next promising step.

Prof. Dr.Dr.Dr. Felix Tretter is Professor for Clinical Psychology at the University of Munich and Vice-President of the Bavarian Academy of Addictions. Formerly he was Senior Physician of a Department for Addiction in a psychiatric hospital; his research interests are addiction, neurobiology, systems science, human ecology and philosophy. He studied Psychology, Medicine and Social Sciences at the University of Vienna and Munich and conducted experimental brain research for several years at the Max Planck Institute for Psychiatry in Munich. felix.tretter@bcsss.org