THE EPIDEMIOLOGY OF EARLY SCHIZOPHRENIA - INFLUENCE OF AGE AND GENDERON ONSET AND EARLY COURSE

For the investigation of the early course of schizophrenia starting fr om onset, the standardised Interview for the Retrospective Assessment of the Onset ofSchizophrenia was developed and validated. In a represe ntative sample of 267 first-admitted German schizophrenics of a broad diagnosis from a population of1.5 million, the age at which different diagnostic and onset definitions weresatisfied, the symptoms at the ti me of the interview, and the accumulation ofpositive and negative symp toms until first admission were assessed. Comparison between the two s exes and three age groups yielded hardly any differences inthe accumul ation of symptoms and their course until first admission, except for a slightly shorter period of negative symptoms in young males and a sli ghtly longer qne in older women -which contradicts prevailing opinion. At the timeof the interview, no significant sex differences were foun d with respect to the core symptoms of schizophrenia (negative and fir st-rank symptoms), but clear and substantial differences emerged in di sease behaviour. The significantly higher age at first onset in women is explained, on the basis of animal experiments and a clinical study, by the neuromodulatory effect of oestrogen on D, receptors and by a h igher vulnerability threshold in women.