H. Häfner - Böcker

This volume is a compilation of the presentations and discus­ sions, arranged in a systematic manner, of the fifth symposium on the Search for the Causes of Schizophrenia, held in Guarujal Brazil in April, 2003. The meetings look back on a great tradi­ tion. The first symposium, held in 1986 on the occasion of the th 600 anniversary of the University of Heidelberg, was our first effort to assemble successful schizophrenia researchers to pre­ sent and discuss research results in a spirit overcoming meth­ odological boundaries and disciplines. The result was one of the most interesting and exciting meetings and a proceedings volume published in 1987. Like the present volume it contained the presentations and discussions of the meeting conveying an excellent picture of what was going on in schizophrenia re­ search at that time and outlining the main future perspectives. Four further symposia followed at an interval of 2 to 3 years each. They were guided by the same principle and characterised by illustrious contributors and a highly stimulating atmosphere. The proceedings volumes, all entitled "Search for the causes of schizophrenia" and looking alike, were published by the same publisher. They reflect the considerable progress made in schi­ zophrenia research since 1986 and have been widely used as a source for information on the most promising research lines and results and as a reference for comprehensive reviews.

H. Hafner, G. Moschel, N. Sartorius The size of the world's population aged over 65 was estimated at about 250 million in 1980; by the year 2025 it is expected to grow to about 760 million (see Hauser, this volume). This sharp increase in life expectancy at birth, in some countries amounting to almost 100% in only a hundred years, has resulted from better nutrition and improved living conditions, hygiene and medical care. Not only life expectancy at birth, but also further life expectancy in advanced age has shown a clear, though more moderate increase. This increased life expectancy, together with a simultaneous fall in birth rates, has caused the mean age of the world population and, especially, the average age of the population of industrial nations to climb substantially in recent times, a development which will reach its peak only some decades from now. For these demographic reasons alone, health care authorities will have to devote more attention to the health problems of the elderly. The main task of medical research is to develop improved methods of disease prevention and treatment. Yet, because the full benefits of such research are only realized after many years of work, researchers have already begun to respond to demographic pressures by focussing part of their efforts on the study of illnesses characteristic of old age.