Department of Medical Psychology and Psychiatry, First Medical School, University of Naples, 80138 Naples, Italy
The issue of the nature of schizoaffective psychoses, and of their relationship to schizophrenia and to major affective disorders, remains one of the most con­troversial of contemporary psychiatry. During the past few years, we have repeatedly emphasized that much of the disagreement existing on this topic can be ascribed to three factors (17): (a) the different solutions given to the question of the boundary between schizophrenia and major affective disorders, (b) the discrepancy between the criteria used by the various authors for the diagnosis of schizoaffective disorders; and (c) the intrinsic heterogeneity of schizoaffective syndromes. We have documented the importance of factor (a), from a historical viewpoint, by looking at the evolution of the concept of schizoaffective disorder in the American literature (14). In this evolution, three phases can be singled out. The first phase, which can be called pre-Bleulerian, is that period preceding the publication in the United States of Bleuler’s Textbook of Psychiatry, which occurred in 1923. In this period, the mixed psychotic syndromes described in the literature, such as remitting catatonic syndrome (12) and benign stupor (10), were unanimously regarded as subtypes of manic-depressive illness. It is easy to realize that such interpretation was influenced by Kraepelin’s comprehensive concept of manic-depressive insanity, and by his delineation, instead, of a very narrow category of dementia praecox. The second phase, which can be called Bleulerian, starts with the publication of Bleuler’s Textbook and covers the following 40 years. During this period, mixed psychoses were included under the heading of schizophrenia, in conformity with the broad Bleulerian conception of this illness. This interpretation is explicit in the papers by Vaillant (26) and is formalized in DSM-I (2) and DSM-II (3). The third phase of the evolution of the concept covers the period between the late 1960s and the early 1970s. In those years, several factors concurred to support a further revision of the boundary between schizophrenia and major affective disorders. Thus, during the 1970s, a narrowing of the concept of schizophrenia and a broadening of that of affective disorders gradually occurred in the United States. Consistent with this change has been the shift of schizoaffective disorders from the schizophrenic area to the affective domain. This shift, supported by the papers by Abrams and Taylor (1), Pope et al. (21), and Rosenthal et al. (22) has been finally formalized in DSM-IH (4), in which schizoaffective disorders are in practice equalized to major affective disorders with mood incongruent psychotic features. Thus, to sum up, it can be said that American psychiatry has been at first Kraepelinian, then Bleulerian, and then again Kraepelinian in its attitude toward the question of the boundary between schizophrenia and major affective disorders, and that such vicissitudes have deeply influenced the prevalent opinion of Amer­ican psychiatrists about the nature of schizoaffective disorders. The importance of factor (a) mentioned at the beginning of this chapter is, therefore, documented. The importance of factor (b), that is, the discrepancy between the criteria used by the various authors for the diagnosis of schizoaffective disorders, has been shown by us by means of a study of the effectiveness of lithium prophylaxis in schizoaffective disorders, carried out by a so-called polydiagnostic approach (15). We selected a sample of 38 patients fulfilling the broad definition of schizo­phrenic psychosis, schizoaffective type provided by ICD-9 (29), and we applied simultaneously to these patients three different sets of operational diagnostic criteria for schizoaffective disorder, that is, Research Diagnostic Criteria (RDC) (24), Kendell’s criteria (6), and the criteria of Welner et al. (28). All patients were treated for 2 years with lithium carbonate, conventional form, and main­tained at plasma lithium levels of 0.6 to 1.0 mEq/1. We found a significant difference between the lithium treatment period and the prelithium period with respect to the mean number of morbid episodes and the mean total morbidity in the whole patient group as well as in the subjects fulfilling RDC and Kendell’s criteria, but not in the patients meeting the criteria of Welner et al. (which emphasize the schizophrenic component of schizoaffective symptomatology). The role that can be played by the diagnostic criteria used for patients’ selection in conditioning the research findings for schizoaffective dis­orders is thus apparent. The importance of factor (c), that is, the intrinsic heterogeneity of schizoaf­fective syndromes, has been documented by our group by means of a study exploring the course and the long-term outcome of patients with a RDC cross-sectional diagnosis of schizoaffective disorder compared with subjects with a RDC cross-sectional diagnosis of major affective disorder (16). Four groups of patients entered this study. The schizomanic group consisted of the 23 patients fulfilling RDC for schizoaffective disorder, manic type, referred to our Center for Prevention and Treatment of Affective Disorders from January 1, 1979 to December 31, 1981. The schizodepressive group consisted of the 24 patients meeting RDC for schizoaffective disorder, depressed type, referred to the center during the same period. The manic and the depressive group included, respectively, the first 23 patients fulfilling RDC for manic disorder and the first 74 patients meeting RDC for major depressive disorder referred to the center during this period. Thirty-six of the schizoaffective patients (17 schizomanics and 19 schizode-pressives) and 39 of the affective patients (16 manics and 23 depressives) com­pleted a 3-year follow-up period. Eleven schizoaffectives and eight affective pa­tients were dropouts. The latter did not differ significantly from the others with respect to sex, age, and severity of the index episode. During follow-up, patients were examined bimonthly. Their psychopathological state was assessed on the occasion of each visit by the Comprehensive Psychopathological Rating Scale (CPRS) (5). New morbid episodes were recorded and classified according to RDC. Within the schizomanic group, eight patients presented new episodes during thee follow-up period. In three cases, they were only schizomanic, in one case both schizomanic and schizodepressive, in two cases schizomanic and depressive, in one case schizomanic, manic, and depressive. Only one patient showed a pure schizophrenic episode. Within the schizodepressive group, 12 patients pre-sented new episodes during the follow-up period. In eight cases, they were only chizodepressive, in two cases schizodepressive and schizophrenic, in one case chizodepressive and depressive. Only one patient showed a manic and a de­pressive episode. In patients with a cross-sectional diagnosis of manic or major depressive disorder, no schizoaffective or schizophrenic episode was recorded during follow-up. These data demonstrate that patients diagnosed cross-sectionally as schizoaf­fective turn out to represent a very heterogeneous group when they are studied longitudinally, which supports the usefulness of a multiaxial approach to the diagnosis and classification of these conditions, taking into account both the cross-sectional symptomatology and the course, such as that recently proposed by Maj and Penis (19). At the end of the follow-up period, the outcome, evaluated by means of the Strauss-Carpenter Outcome Scale (25) and the Disability Assessment Schedule (11), was not significantly different (although somewhat poorer) in schizomanics as compared with manic patients, whereas it was significantly worse in schizo-depressives as compared with patients diagnosed cross-sectionally as depressives. Th
ese findings support the view that although schizomania is probably closely allied to bipolar affective disorder, the inclusion of schizodepressive disorder under the heading of major affective disorders is not justified. This conclusion is supported also by the results of another study by our group (18), showing that the presence of mood incongruent psychotic features during the index episode in patients with a DSM-III diagnosis of major depression, recurrent, is a predictor of poor response to lithium prophylaxis, whereas the presence of the same psy­chotic features in the index episode of patients with a DSM-III diagnosis of bipolar disorder is not associated with an unfavorable response to prophylaxis. Starting from this evidence that schizoaffective disorder, depressed type, rep­resents a heterogeneous group of syndromes, only part of which are related to major affective disorders, we have tried, during the last two years, to characterize schizodepressive patients from the biological and neuropsychological point of view. Here we report some data concerning the response on dexamethasone suppression test (DST) and the performance on the Luria-Nebraska Neuropsy­chological Battery (LNNB) (7) in this category of patients. DST has been frequently proposed, during the past few years, as a tool for the identification of a homogeneous subtype of schizodepressive disorder. In fact, it has been suggested (8,23) that nonsuppression on DST would characterize a subgroup of schizodepressive patients closely resembling pure melancholies in their clinical features, and frequently showing a family history of affective dis­orders, a good short-term outcome, and a favorable response to antidepressants. Our study was carried out in 20 patients fulfilling RDC for schizoaffective disorder, depressed type, 52 patients with a RDC diagnosis of major depressive disorder, and 20 normal controls. DST was performed by administering 1 mg dexamethasone at 11 P.M., and drawing a blood sample at 4 P.M. of the following day. Plasma Cortisol levels were determined by radioimmunoassay. Nonsuppres­sion was defined as a postdexamethasone plasma Cortisol concentration higher than 50 ng/ml. Nonsuppression on DST was observed in 25% of schizodepressive patients, in 40.4% of patients with major depression, and in 5% of controls. As suppressor and nonsuppressor schizodepressives were compared with respect to historical variables, no significant difference was observed. In particular, a personal history of previous manic episodes (bipolar course) was observed in one suppressor (6.7% of the sample) and none of nonsuppressors; a personal history of previous pure major depressive episodes in two suppressors (13.3%), and one nonsup­pressor (20%); a family history of major affective disorders in two suppressors (13.3%) and one nonsuppressor (20%). The mean number of RDC symptoms for endogenous depression was about the same in the two subgroups, as well as the total score on the Hamilton Rating Scale for Depression (9) and the scores on CPRS depressive and "schizophrenic" items, both at the time of DST and 3 months later. Of eight schizodepressives who could be classified as "mainly af­fective" according to RDC, six were suppressors and two nonsuppressors, and of four "mainly schizophrenic" schizodepressives, three were suppressors and one nonsuppressor. Thus, the results of our study do not support the usefulness of DST for the identification of a subtype of schizoaffective disorder, depressed type, more closely allied to "pure" major depression. Our neuropsychological investigation consisted of two parallel studies. In study 1, four groups of subjects were administered the LNNB: 16 patients with a RDC diagnosis of major depressive disorder, 20 patients with a RDC diagnosis of schizophrenia, and 20 normal controls. In study 2, the same battery was used in 15 patients with a former RDC diagnosis of schizoaffective disorder, depressed type, and 15 patients with a former RDC diagnosis of major depressive disorder, both examined during a phase of remission, from 2 to 4 years after the index episode. In study 1, the performance of schizodepressive patients was intermediate between that of schizophrenics and that of depressives with respect to all the scales except one (Visual). No significant difference was observed between schizodepressives and either of the other patient groups. This finding may be interpreted in different ways. In any case, it is consistent with the view that RDC schizodepressive disorder encompasses a heterogeneous group of syndromes, which vary in their relationship to major depression and to schizophrenia. More interesting are the results of the second study, that is, of the comparison of remitted schizodepressives and "pure" depressives, examined from 2 to 4 years after the index episode. As a matter of fact, former schizodepressives showed a significantly worse performance on the scales Memory and Intellectual processes of the LNNB. No significant difference was observed between former depressives and a group of normal controls matched for sex, age, and educational level. It seems, therefore, that whereas patients with "pure" major depression tend to make a complete recovery from their episodes, without any cognitive deterio­ration, some impairment of cognitive functions may, instead, persist in schizo­depressive patients. In conclusion, the results of our studies support the view that although most cases of schizomania can be interpreted as variants of bipolar affective disorder, schizoaffective depression represents a heterogeneous group of syndromes, whose inclusion under the heading of major affective disorders is not justified. As a matter of fact, schizodepressive patients, as compared with "pure" depressives, show, on average, a poorer long-term outcome, a worse response to lithium prophylaxis, and a poorer performance on cognitive tests after remission. Most probably, some of the cases that are defined cross-sectionally as schizo­depressive are, in fact, cases of schizophrenia with superimposed depression. It is indeed well-known that the frequency of depression is particularly high in schizophrenic patients, in which it has been regarded by the different authors as an integral part of schizophrenic illness (13), as a consequence of the recovery of insight after acute psychotic episodes (20), or as an effect of long-term neu­roleptic treatment (27). DST, according to our data, does not appear to be useful for the identification of a more homogeneous subtype of schizodepressive disorder. We are now exploring the possible significance as predictors of long-term outcome of several aspects of the cross-sectional symptomatology and of the course of the illness in schizodepressive patients.
(more…)