[Sex differences in schizophrenic diseases]

Sex differences in schizophrenic diseases have been known for a long time but have also been subject to long-term neglect by psychiatric epidemiological research, although a study of these sex differences could, in our opinion, yield valuable pointers to pathogenic factors involved in this group of diseases the aetiology of which still awaits clarification. For this reason we initiated large-scale investigations focussed on this topic. The paper presented here discusses a few initial results, basing on data of Mannheim and National Danish Case Records and on our own study on schizophrenia, the latter being a representative record of 392 patients hospitalised for the first time in the Rhine-Neckar region and the eastern part of the Palatinate. First of all, sex differences at the age at which the disease appeared for the first time, were studied while paying close attention to artifacts and other, usually neglected methodical error sources. The difference in the average age of the sexes at first hospitalisation was confirmed, and also--using an instrument specially developed for that purpose--at the onset of the disease. At the time the first signs of the disease are noticed and the first schizophrenic symptoms become apparent, men are about 3 to 4 years younger than women. On the other hand, the cumulative lifetime risk--calculated up to 60 years of age--seems to be the same for both sexes. It appears that there are no sex differences in the pattern of symptoms of the disease at the time of initial hospital admittance, in respect of both the most common and the characteristic signs and symptoms. There were significant although quantitatively not very great differences in respect of patient behaviour which displays socially positive aspects somewhat more often in women and socially negative ones distinctly more often in men. In respect of the course of the disease we could not find any marked sex differences over a period of 10 years after onset of the disease; however, this is presently based only on the Danish case record data and on criteria of the course of the disease, such as number and duration of inpatient treatments.