The phenomenology of manic-depressive insanity or bipolar disorder has been remarkably consistent for more than 2,000 years, including descriptions of blatantly psychotic behaviors and a chronic course. Yet some physicians in the mid-1800s began to use a different diagnosis, dementia praecox or schizophrenia, to designate cases of psychosis with a chronic, deteriorating course in young people progressing to a state of “dementia.” In retrospect, these cases may have consisted of the most severely affected bipolar patients and not a separate disease.
Emil Kraepelin established a keystone of psychiatry (ie, his dichotomy), validating bipolar disorder and schizophrenia as bona fide and separate diseases. Bleuler may have been influenced to choose to name and promote schizophrenia rather than bipolar disorder because schizophrenia was considered a more devastating and important disease than bipolar. Some now consider Bleuler’s choice of schizophrenia unfortunate because his influence magnified the importance of schizophrenia over bipolar disorder for almost 100 years. Schneider reaffirmed Bleuler’s idea that psychosis and chronicity were pathognomonic of schizophrenia and incompatible with a core disorder of mood.
The severity of symptoms, family disruption, and poor prognosis for patients diagnosed with schizophrenia instead of bipolar disorder, coupled with the costs for long-term care and disability status of schizophrenia, have garnered considerable attention since the 1950s from government, politicians, taxpayers, celebrities, the media, and society in general. As a result, hundreds of millions of federal dollars have funded research on schizophrenia. Similar numbers of pharmaceutical dollars have supported the development and clinical trials of new antipsychotic drugs. Although discovered about the same year (1949–1950), the widespread use of chlorpromazine (Thorazine) for schizophrenia in the United States predated by 2 decades the widespread use of lithium for bipolar disorder. These factors stimulated increased diagnoses and research on schizophrenia that generated lectures, seminars, publications, grant applications, and further diagnoses and funding for schizophrenia rather than bipolar disorder. Also noted by Craddock et al, “… substantially greater resources and samples have been used to date on studies of schizophrenia [than bipolar disorders].” They also address the resultant bias stating that, “It has been conventional for psychiatric research, including the search for predisposing genes, to proceed under the assumption that schizophrenia and bipolar disorder are separate disease entities with different underlying etiologies. These represent Emil Kraepelin’s traditional dichotomous classification of the so-called ‘functional’ psychoses.”1 Until recently, such presumptions have resulted in strong research bias in comparative studies for reporting differences and ignoring similarities and overlap. For example, family studies were initially misinterpreted to conclude that schizophrenia and bipolar disorder “breed true,” and for decades, this was a major source of support for the dichotomy. Recent large studies have reversed this initial idea, but the original results that schizophrenia and bipolar disorder breed-true has been taught for years.
Similarly, in many other initial “positive” studies of “schizophrenia,” the patients with schizophrenia were compared with healthy volunteers, giving credence to schizophrenia as a bona fide disease. A more accurate interpretation of such data may be that patients with psychoses are different from persons without psychoses. Subsequent studies of patients with psychotic bipolar disorder often found results similar to those initially thought unique to schizophrenia. Of note is that psychotic bipolar differs from non-psychotic bipolar in some measurements. Thus, the psychotic group diagnosed with schizophrenia may have suffered from psychotic bipolar disorder, not a different disease called schizophrenia. For example, an increased ventricle-to-brain ratio and at least two susceptibility loci, D-Amino Acid Oxidase Activator (DAOA/G30) and Disrupted in Schizophrenia-1 (DISC-1), were initially associated with schizophrenia but were subsequently found to be linked with psychotic bipolar disorder.1–4 That the DISC-1 locus was so named serves as an excellent example of this concept that schizophrenia was studied initially and positive results mistakenly assumed to support schizophrenia as different from a psychotic mood disorder.
Some results showing two separate disorders may be explained by differences between psychotic bipolar disorder (misdiagnosed as schizophrenia because of psychotic symptoms) and non-psychotic bipolar disorder. The DAOA/G30 locus, again, exemplifies this because it is reported in patients with psychotic bipolar disorder but not non-psychotic bipolar disorder.1–4 One group showed that almost 80% of functionally psychotic inpatients suffer from a psychotic mood disorder rather than schizophrenia or schizoaffective disorder.5 Although these data are radically contradictory to the traditional teachings of Bleuler and Schneider, they are supported by many other researchers through the decades.6–13 Despite this apparent support for the unitary hypothesis, the statement by Pope and Lipinski still appears unfulfilled today: “The over diagnosis of schizophrenia and under diagnosis of bipolar disorder is a particularly serious problem in contemporary America. There are no known pathognomonic symptoms for schizophrenia, nor even any cluster of symptoms … to be valid in diagnosing schizophrenia. The non-specificity of ‘schizophrenic’ symptoms brings into question all research that uses them as the primary method of diagnosis.”
The misunderstanding that “a touch of schizophrenia (psychosis) is schizophrenia” has been regrettable. Mood symptoms may not be pursued or can be obscured in psychotic patients or may be assumed secondary to the schizophrenia. Schizophrenia has been taught as a disorder of thought and mood disorders taught as disorders of the emotions. Most critical to the longevity of schizophrenia has been the tradition that a disorder of thought and a diagnosis of schizophrenia trumps diagnoses of disorders of mood. Now, many accept that mood disorders are also disorders of thought.12 It may be appropriate to change the original concept noted above to “a touch of a mood disturbance (in psychotic patients) is a psychotic mood disorder.” However, noted recently, “Unfortunately, once a diagnostic concept, such as schizophrenia … has come into general use, it tends to become reified. That is, people too easily assume that it is an entity whose validity need not be questioned.”14
The dichotomy has been established and accepted for so long that such a major change to only one disease instead of three naturally meets with strong resistance. Molecular genetics may hold the greatest promise to solve the dilemma, but for now, the primary factor inhibiting the rejection of the dichotomy and the validity of schizophrenia as a separate disease is, of course, the lack of any measurable pathophysiology for either disease. Nevertheless, this author believes there are now enough data suggesting similarities that the current discussion is warranted. As previously noted, the dichotomy is attractive to clinicians because it is “conceptually simple and allows psychiatrists to demonstrate diagnostic expertise by exercising judgment over an often complex clinical picture and to reach a clear diagnosis.”2 Swartz, however, emphasizes the variability in clinical judgment based on the diagnostician’s training. Most of us were taught to focus upon psychotic symptoms and to diagnose schizophrenia when psychotic symptoms were present. The following two cases are examples13 of how schizophrenia can be misdiagnosed based on this traditional misconcept that psychosis means schizophrenia.
A 56-year-old unemployed house painter, escorted to the emergency department by the police, was voluntarily admitted to the psychiatric ward because he said “the devil is coming to take me away.” A passerby had called the police after seeing this man standing suspiciously on a bridge. Claiming that he deserved to die, he wanted to jump to his death “before the devil got him.” He was unshaven, unclean, and emaciated. On the unit, his affect remained terrified, tearful, and suspicious; he would not accept anything by mouth. He said that he heard voices of the devil and God arguing over who should kill him. He said that he heard the devil say that he was “coming up the hospital stairs” and “had corrupted the nursing staff.” He was diagnosed with schizophrenia, paranoid type or post-schizophrenic depression, and forcibly treated intra-muscularly with haloperidol (Haldol). As he began to improve, he endorsed the symptoms of a major depressive episode. Some believed that his diagnosis should be changed to major depressive disorder, severe with psychotic features, but others thought that the importance of the psychosis was the more critical diagnostic issue mandating the diagnosis of schizophrenia. Nine months later, he was readmitted in handcuffs and was grossly psychotic, disorganized, and was speaking in tongues. His wife had called the sheriff after he had a dump truck fill their entire front yard with 10,000 fresh oysters in the shell. The patient exhibited racing thoughts, pressed speech, irritability, and said that he had not slept “for weeks” while planning a party for the state legislature and governor. His diagnosis and medications were changed. Lithium combined with valproic acid (Depakote) stabilized his mood. The patient might have retained his misdiagnoses and inappropriate pharmacotherapy had he presented to a psychiatrist who focused on the past diagnosis and the present psychosis, disorganization, and positive Schneiderian criteria.
This 36-year-old, multiply divorced female nurse was brought by ambulance to the ED and was unconscious after an overdose of benzodiazepines. After 3 days on a ventilator and 3 more days in the intensive care unit, she was transferred to psychiatry. There, she said that she wanted to die at her own hands “rather than be arrested by law enforcement, imprisoned, and sentenced to death in the electric chair.” She believed that her death was imminent. She had suddenly stopped going to work for fear of being apprehended and arrested. She had suffered several hospitalizations, with the diagnosis of chronic paranoid schizophrenia, which was assigned at this admission as well. Post-schizophrenic depression was also considered. The patient said that once her “incompetence was discovered by her hospital administration, she would be prosecuted and executed for murder.” She felt that she deserved to be punished but was afraid of death. Her “crime” involved the death of a 4-year-old child suffering from terminal leukemia and under her hospice care.
Upon careful questioning, the patient admitted to past episodes of decreased need for sleep, increased activities, racing thoughts, the ability to work three jobs at once without fatigue, and poor decisions with dangerous outcomes, such as unprotected sex with unknown men. These episodes lasted several months and were usually followed by severe depressions. Only because of these follow-up questions was her diagnosis changed to bipolar disorder-I, depressed, severe with psychotic features. Stability of her mood required lithium, carbamazepine (Tegretol), and lamotragine (Lamictil).
Although “post-schizophrenia depression” is no longer in the Diagnostic and Statistical Manual of Mental Disorders (DSM), it remains in the International Classification of Diseases, 10th edition (ICD-10) as a subtype of schizophrenia. This speaks to the effect of Bleuler and Schneider in associating psychosis with schizophrenia rather than mood disorders. Post-schizophrenic depression is likely a severe depression with psychotic symptoms or post-psychotic depression. The psychotic symptoms may have initially obscured mood symptoms, but, upon even partial remission of the psychosis, symptoms of the core mood disorder become more obvious. Some authors report no differences between psychotic depression and schizophrenia, implying that they are the same disorder with different names. The diagnoses often depend upon the training of the diagnostician, as seen in the case examples above.15
Another factor in the longevity of the concept of schizophrenia is that the power base of researchers, academics, editors, and administrators invested in schizophrenia has been greater and more influential than that of those studying other psychiatric disorders. Schizophrenia has received media attention in the news and in film and has been evoked as the explanation for numerous high-profile murders, despite notations of behaviors in the press compatible with either mania or depression. The term “schizophrenic” is misused as an adjective in the media and by the public to signify “flip-flops” in behaviors, statements, or policies usually involving politics. For reasons such as these, schizophrenia has maintained its place as the most widely known mental disorder in the world.
A Lesson from Multiple Sclerosis and Syphilis
The lessons from multiple sclerosis and syphilis establish a basic tenet in medicine (ie, when one disease can explain a variety of symptoms, there is likely only one disease). The variability of presenting symptoms and course of these two diseases prevented initial recognition of each as a single disease. Similarly, patients diagnosed with schizophrenia or schizoaffective disorder may suffer from a severe, psychotic, mood disorder and not different disorders.
Suggested Changes for DSM-V
As previously reported, the degree and breadth of commonality among the three psychotic psychiatric disorders are provocative and appear to justify this final step in the changing concept about choosing a diagnosis for psychotic patients. The hypothesis that a mood disorder accounts for all three psychotic disorders eliminates many of the inconsistencies in comparative research results, obviates subtypes of schizophrenia and schizoaffective disorder and allows a consolidation of diagnoses (see the Table, page 139, and the Sidebar, page 140).
Table. Hierarchy of Severity (from Highest to Lowest)
Proposed Additions to the DSM Specifiers for Mood Disorders
Severity: Mild (.x1); moderate (.x2); severe, without psychotic features (.x3); severe with mood congruent(.x4)/incongruent psychotic features (.x5)*; partial (.x6), full remission (.x7)
Course: Non-chronic/chronic (symptoms > 2 years); SAD**; rapid cycling; postpartum onset, with/without full interepisode recovery
Features: catatonic; paranoid/grandiose; disorganized; undifferentiated; melancholic; atypical
* = proposed additions (shown in bold font) ** = SAD = seasonal affective disorder
This review proposes a consolidation of diagnoses with a simplified hierarchy of diseases for psychotic patients that uses only mood disorders, in contrast to using all three of the traditional psychotic disorders diagnoses (see the Table, page 139, and the Sidebar, page 140). Bipolar-I, bipolar-II, depressed and major depressive disorders, severe with mood incongruent psychotic features, chronic, with or without treatment resistance could replace the various schizophrenic and schizoaffective disorder diagnoses. Expansion of the “specifiers” for mood disorders may be prognostically useful. Mood incongruent versus mood congruent psychoses, chronic versus non-chronic, and “with” versus “without treatment resistance” seem to predict more severe prognoses.16 Congruency is already included in the DSM-IV-TR but is not assigned a fifth digit code. Assigning “.x4” as “severe with mood congruent psychotic features,” “.x5” as “severe with mood incongruent psychotic features” and increasing the fifth digit by one for “in partial remission” to .x6 and “in full,” to .x7 would emphasize congruency to accommodate the transition from schizophrenia and schizoaffective disorder to severe mood disorders. “Non-chronic” might be a productive addition to “chronic,” which is already present in DSM with the goal of adding focus to “course.” Catatonia has been given as a potential “feature” for mood disorders for more than 10 years. If desired for further historical continuity, the other conventional subtypes of schizophrenia, more likely accounted for by psychotic mood disorders, might be added to the “features” subsection of “specifiers” for additional descriptors for very severe psychotic mood disorders when disorganization, paranoia/grandiosity or none of these (undifferentiated) predominate diagnoses (see the Table, page 139, and the Sidebar, page 140).
Although some participants in the DSM-V planning meeting titled “Deconstructing Psychosis” in February 2006 stated either that the concept of schizophrenia be abandoned or could not be distinguished from bipolar disorder, schizophrenia continues to be the most recognized mental illness in the world. Although the massive volume of data on “schizophrenia” inhibit doubt of its credibility, all research on schizophrenia has been questioned based on the overlap of diagnostic symptoms with psychotic bipolar disorder.9 This massive volume of literature is not a sound scientific basis to continue to recognize schizophrenia. The current data support the suggestion of moving the remaining subtypes of schizophrenia (paranoid, disorganized, and undifferentiated) to the “features” section of mood disorders and eliminating schizophrenia and schizoaffective disorder from the DSM-V diagnoses (see the Table, page 139, and the Sidebar, page 140). Substitution of “psychosis” for “schizophrenia” appears warranted. The continuum, dimensional, or spectrum approach is appropriate but might be applied to the mood disorders with regard to severity of symptoms and chronicity of course. According to several researchers, the categorical approach is accurate for those psychiatric disorders that have scientific support as bona fide; diagnoses, such as the neuroses of past decades and now schizoaffective disorder and schizophrenia, have not met criteria for acceptance as bona fide and separate from psychotic mood disorders.6–17 Applying the dimensional approach to the psychoses (maintaining schizophrenia and schizoaffective disorder) rather than to mood disorders fails to emphasize the importance of the use of mood-stabilizing medications. As noted above, one report indicates that a majority of functionally psychotic patients have a psychotic mood disorder.5 This percentage might be taken as representing a upward trend, with schizophrenia approaching zero. Because there are established endophenotypic differences between psychotic and non-psychotic mood disordered patients, the “dichotomy” may be between psychotic and non-psychotic mood disordered patients and not schizophrenia. The liabilities for patients misdiagnosed with schizophrenia, their families, their physicians and society are substantial.
- Craddock N, O’Donovan M, Owen M. Genes for schizophrenia and bipolar disorder? Implications for psychiatric nosology. Schizophren Bull. 2006;32(1):9–16. doi:10.1093/schbul/sbj033 [CrossRef]
- Craddock N, Owen M. Rethinking psychosis: the disadvantages of a dichotomous classification now outweigh the advantages. World Psychiatry. 2007;6(2):84–91.
- Schurhoff F, Szoke A, Meary A, et al. Familial aggregation of delusional proneness in schizophrenia and bipolar pedigrees. Am J Psychiatry. 2003;160(7):1313–1319. doi:10.1176/appi.ajp.160.7.1313 [CrossRef]
- Schulze TG, Ohlraun S, Czerski P, et al. Genotype-phenotype studies in bipolar disorder showing association between the DAOA/G30 locus and persecutory delusions: a first step toward a molecular genetic classification of psychiatric phenotypes. Am J Psychiatry. 2005;162(11):2101–2108. doi:10.1176/appi.ajp.162.11.2101 [CrossRef]
- Pini S, Cassano GB, Dell’Osso L, Amador XF. Insight into illness in schizophrenia, schizoaffective disorder, and mood disorders with psychotic features. Am J Psychiatry. 2001;158(1):122–125. doi:10.1176/appi.ajp.158.1.122 [CrossRef]
- Specht G. Chronic mania and paranoia. ZBL. Nervenheilk. 1905;28:590.
- Kendell RE, Gourlay J. The clinical distinction between the affective psychoses and schizophrenia. Br J Psychiatry. 1970;117(538):261–266.
- Ollerenshaw DP. The classification of the functional psychoses. Br J Psychiatry. 1973;122(570):571–530. doi:10.1192/bjp.122.5.517 [CrossRef]
- Pope HG, Lipinski JF. Diagnosis in schizophrenia and manic-depressive illness, a reassessment of the specificity of “schizophrenic” symptoms in the light of current research. Arch Gen Psychiatry. 1978;35(7):811–828.
- Brockington IF, Wainwright S, Kendall RE. Manic patients with schizophrenic or paranoid symptoms. Psychol Med. 1980;10:73–83. doi:10.1017/S0033291700039611 [CrossRef]
- Lake CR, Hurwitz N. 2 Names, 1 Disease: Does schizophrenia = psychotic bipolar disorder?Current Psychiatry. 2006;5:43–60.
- Lake CR. Disorders of thought are severe mood disorders: the selective attention defect in mania challenges the Kraepelinian dichotomy — a review. Schizophren Bull. 2008; 34:109–117. doi:10.1093/schbul/sbm035 [CrossRef]
- Lake CR. Hypothesis: grandiosity and guilt cause paranoia; paranoid schizophrenia is a psychotic mood disorder; a review. Schizophren Bull. 2008;34(6):1151–1162. doi:10.1093/schbul/sbm132 [CrossRef]
- Kendell R, Jablensky A. Distinguishing between the validity and utility of psychiatric diagnoses. Am J Psychiatry. 2003;160(1):4–12. doi:10.1176/appi.ajp.160.1.4 [CrossRef]
- Swartz CM, Shorter E. Psychotic Depression. New York, NY: Cambridge University Press; 2007.
- Lake CR., Hurwitz N. Schizoaffective disorders are psychotic mood disorders; there are no schizoaffective disorders. Psychiatry Res. 2006;143(2–3):255–287. doi:10.1016/j.psychres.2005.08.012 [CrossRef]
- Bentall RP, Jackson HF, Pilgrim D. Abandoning the concept of “schizophrenia:” some implications of validity arguments for psychological research into psychotic phenomena. Br J Clin Psychol. 1988;27(Pt 4):303–324.
Hierarchy of Severity (from Highest to Lowest)
|Schizophrenia, non-chronic/chronic, catatonic, paranoid, undifferentiated, or disorganized type||BP I, manic, depressed or mixed, severe, without/with mood cong/incong psychotic features, non-chronic/chronic; catatonic, paranoid, undifferentiated or disorganized type|
|SA D/O, mainly schizophrenia, non-chronic/chronic||BP II, depressed, severe, without/with mood cong/incong psychotic features, non-chronic/chronic|
|SA D/O, BP/mainly affective, depressed with cong/incong psychotic features, non-chronic/chronic||MDD, recurrent, severe, without/with mood cong/incong psychotic features, non-chronic/chronic|
|SA D/O, BP/mainly affective, manic with cong/incong psychotic features, non-chronic/chronic||MDD, single episode, severe, without/with mood cong/incong psychotic features, non-chronic/chronic|
|BP I, manic, depressed or mixed, severe, without/with mood cong/incong psychotic features, non-chronic/chronic||BP II, hypomanic, non-chronic/chronic|
|BP II, depressed, severe, without/with mood cong/incong psychotic features, non-chronic/chronic||Cyclothymia|
|MDD, recurrent, severe, without/with mood cong/incong psychotic features, non-chronic/chronic||Dysthymia|
|MDD, single episode, severe, without/with mood cong/incong psychotic features, non-chronic/chronic||Euthymia|
|BP II, hypomanic, non-chronic/chronic|