Course of unipolar depressive, bipolar manic-depressive, and schizoaffective disorders. Results of a prospective longitudinal study (author's transl)

Abstract

A prospective longitudinal study of the course of affective disorders was conducted from 1959-1975, based on 159 unipolar depressions, 95 bipolar manic-depressive disorders and 150 schizoaffective psychoses. These three groups of patients did not differ significantly from each other in respect of age (approximately 60 years) and sex distribution. On the other hand, there are marked differences in respect of period of observation and duration of the disorder as a result of differences in the age when the disease became manifest for the first time. Unipolar depressions take a much more favourable course than bipolar and schizoaffective ones, the last two resembling each other in many characteristic aspects. Unipolar depressions begin on the average when the patient is 45 years old, whereas onset of the bipolar disorders is at the age of 35 and of the schizoaffective psychosis at 32. The duration of disease of unipolar depressions is markedly shorter than that of the other two groups. In many cases, unipolar depressions will also recover spontaneously (in about 40% of the cases.) In this group, however, we also find the definitely highest incidence rate of suicides (10% for the whole group, 13-14% for patients hospitalised for the first time.) With an average observation period since the first manifestation of the disease of 19 27 years (depending on the disease group) we observed in unipolar depressions four phases in 19 years, in bipolar depressions 9 in 26 and in the schizoaffective psychoses 7 in 27. Here, too, the course of the unipolar disorders is relatively favourable, but there is an additional bias in favour of a more optimistic pattern apart from the incidence of suicides, because of the high age of first manifestation in this group of diseases. A future study will have to show more accurately whether unipolar depressives who fell ill early will be cured more frequently than patients in whom the disease became manifest at a larger age. So far, the suicide incidence is equal in both groups. The duration of the phase was mainly arrived at by intra-individual mean values, which, in turn, were averaged for entire disease groups. Viewed in this sense, unipolar depressive phases have an average duration of 5.95 months, whereas bipolar diseases last for 4.4 and schizoaffective psychoses for 4.65 months. Chronicity in the sense of a duration exceeding twelve or twenty four months is often observed. The last observed phase of the disorder lasted for more than a year in 24.5% of the unipolar, 17.9% of the bipolar and 18.0% of the schizoaffective patients. Within these subgroups, there is a duration of the last phase of more than two years in 17.0% in the unipolar, 13.7% in the bipolar, 12.0% in the schizoaffective patients, i.e. about two-thirds of the one-year phases can last also for more than two years. The time spacings of successive phase beginnings (cycles) revealed a systematic reduction. Initially, they are large, eg more than five years in unipolar disorders and about 4 years in bipolar disorders, but shorten down relatively quickly according to an exponential curve, which is why the phases of the disorder follow one another at shorter and shorter intervals, until a certain limit value, which is intraindividually different, has been attained. However, all patients do not continually suffer from new relapses; there are in fact spontaneous ,,healings", which have been defined as free interval of at least five years since manifestation of the last episode. Such a free interval was observed in 44% of the unipolar, 17% of the bipolar and 37% of the schizoaffective disorders. Despite these partly favourable courses, it must be placed on record that in the majority of cases the disease is still active at an average age of 60 at the point of follow-up. Hence, we cannot expect that further permanent medication eg with lithium for the purpose of prophylaxis, can be omitted when the patient has reached the age of 60. The number of full remissions is far from satisfactory. Contrary to the originally optimistic assumption by Kraepelin that affective psychoses have a good prognosis, it is definite that especially bipolar disorders, particularly of course the schizoaffective ones which are nearer to schizophrenia, register complete remission in a minority of cases only. Complete remissions are seen in unipolar cases in about 41%, in bipolar in 36% and in the schizoaffective psychoses in 27% of the cases. This unfavourable prognostic finding agrees with those made by Shobe and Brion (1971), Tsuang and Winokur (1975) as well as Welner et al.(1977). Modern research into the course of endogenous psychoses shows that the previous notions with regard to the prognosis of schizophrenia were too unfavourable and those regarding the prognosis of the affective disorders were too optimistic.