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Schizoaffective disorder
ICD-10 F25
ICD-9 295.70
OMIM 181500
DiseasesDB [1]
MedlinePlus [2]
eMedicine /
MeSH {{{MeshNumber}}}

Schizoaffective disorder is a psychiatric diagnosis that describes a mental disorder characterized by recurring episodes of elevated or depressed mood, or simultaneously elevated and depressed mood that alternate or occur together with distortions in perception.[1][2] The perceptual distortion component of the disorder, called psychosis, may affect all five senses, including sight, hearing, taste, smell and touch, but most commonly manifest as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking with significant social and occupational dysfunction. The elevated, depressed or simultaneously elevated and depressed mood episode components of the disorder, called mood disorder, are broadly recognized as depressive and bipolar types of the illness; the division is based on whether the individual has ever had a manic, hypomanic or mixed episode. Onset of symptoms usually begins in early adulthood and is rarely diagnosed in childhood (prior to age 13). The lifetime prevalence of the disorder is uncertain (due to studies using varying diagnostic criteria), although it is generally agreed to be less than 1 percent, and possibly in the range of 0.5 to 0.8 percent.[3] Diagnosis is based on the patient's self-reported experiences and observed behavior. No laboratory test for schizoaffective disorder currently exists. As a group, people with schizoaffective disorder have a more favorable prognosis than people with schizophrenia, but a worse prognosis than those with mood disorders.[4]

Studies suggest that genetics, early environment, neurobiology, psychological and social processes are important contributory factors; some recreational and prescription drugs appear to cause or worsen symptoms. Current psychiatric research is focused on the role of neurobiology, but no single organic cause has been found.

The mainstay of treatment is antipsychotic medication combined with mood stabilizer medication or antidepressant medication, or both. Antipsychotic drugs primarily work by suppressing dopamine activity; while antidepressant drugs primarily work by increasing the active levels of at least one monoamine neurotransmitter. The exact mechanism of how mood stabilizers work is uncertain. Psychotherapy, and vocational and social rehabilitation (see psychiatric rehabilitation) are also important for recovery. In more serious cases—where there is risk to self and others—involuntary hospitalization may be necessary, although hospital stays are less frequent and for shorter periods than they were in previous times.[5]

The disorder is thought to mainly affect cognition and emotion, but it also usually contributes to ongoing problems with behavior and motivation. People with schizoaffective disorder are likely to have additional (comorbid) conditions, including anxiety disorders and substance abuse. Social problems, such as long-term unemployment, poverty and homelessness, are common. Furthermore, the average life expectancy of people with the disorder is shorter than those without the disorder, due to increased physical health problems and a higher suicide rate.

The diagnosis was introduced in 1933[6] and will be removed from or amended in the next iteration of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-V), to be published in 2012.[7][8]

Signs and symptoms[]

Late adolescence and early adulthood are the peak years for the onset of schizoaffective disorder, although it has been diagnosed (very rarely) in childhood. These are critical periods in a person's social and vocational development which can be severely disrupted by disease onset.

Schizoaffective disorder is a mental illness characterized by recurring episodes of mood disorder and psychosis. Psychosis is defined by paranoia, delusions and hallucinations. Mood disorders are defined by discrete periods of clinical depression, mixed episodes and manic episodes. Individuals with the disorder may experience psychotic symptoms before, during or (commonly) after their depressive, mixed or manic episodes.

The illness tends to be difficult to diagnose since the symptoms are similar to other disorders with prominent mood and psychotic symptoms like bipolar disorder with psychotic features, recurrent depression with psychotic features and schizophrenia.

There are many similarities between schizoaffective disorder, schizophrenia, bipolar disorder with psychotic features, and recurrent depression with psychotic features. The main similarity between schizoaffective disorder, bipolar disorder with psychotic features, and major depressive disorder with psychotic features, is that in all three disorders psychosis occurs during mood episodes. By contrast, in schizoaffective disorder, as it is presently defined, psychosis must also occur during periods without mood symptoms. In schizophrenia, mood episodes have been thought to be absent or less prominent than in schizoaffective disorder, although this distinction is currently under debate. Since these differences can be difficult to detect, a firm diagnosis of schizoaffective disorder may thus require an extended period of observation and treatment.

Untreated, the individual with schizoaffective disorder may experience delusions. It should be noted that delusions in schizoaffective disorder are acute manifestations of an active psychosis and are not personality traits; that is, they go away when the psychosis subsides. Manifestations of delusions include the individual being convinced that he or she is Jesus or the Antichrist, has some special purpose or destiny (such as to save the world), or is being monitored, watched or persecuted by something (commonly governmental agencies), when in reality they are not. Individuals may also feel extremely paranoid. Other delusions may include the belief that an external force is controlling the individual's thought processes. (See thought insertion.)

Hallucinations involving all five senses can also occur in untreated or undertreated schizoaffective disorder. That is, the individual may see, hear, smell, feel or taste things that aren't there. For example, the individual may see overt visual hallucinations such as monsters, the devil or more subtle ones such as shadowy apparitions. Individuals may hear voices or, in some cases, music. Things may look or sound different. Individuals may also experience strange sensations. These hallucinations may worsen when the individual is intoxicated.

The untreated individual may quickly change their mind about their romantic partner, friends or family if they hear something negative being said about them; as a result they may attack or, conversely, isolate themself from the person or group until they regain normal thoughts, which usually takes treatment and time.

Comorbid or co-occurring anxiety disorders may also play a role in the subjective experience of schizoaffective disorder and thus may shape the individual's delusional thought content. For example, the individual may feel anxious, have trouble swallowing, and then believe that outside forces are controlling their throat functions. They may also suffer from various phobias which may also manifest as delusions.

There may be a decline in work or school functioning during episodes of illness. As stated above, individuals with schizoaffective disorder may withdraw socially and become isolated.

The untreated individual may sleep too much, or (more often) be unable to sleep.

Difficulties with thinking known as "cognitive deficits" (see executive function) may also be a problem for individuals with schizoaffective disorder. This may include difficulties with concentration, attention, logical reasoning and impulse control.

Without treatment, the individual with schizoaffective disorder may further worsen in their delusional thought processes and become further alienated from people and society.

With comprehensive treatment, many individuals with schizoaffective disorder may recover much, most or even all of their functionality.

Diagnosis[]

Diagnosis is based on the self-reported experiences of the person as well as abnormalities in behavior reported by family members, friends or co-workers to a psychiatrist, psychiatric nurse, social worker or clinical psychologist in a clinical assessment. There is a list of criteria that must be met for someone to be so diagnosed. These depend on both the presence and duration of certain signs and symptoms.

As discussed above, there are several psychiatric illnesses which may present with a similar range of psychotic symptoms; these include bipolar disorder with psychotic features, major depression with psychotic features, schizophrenia, drug intoxication, brief drug-induced psychosis, and schizophreniform disorder. These disorders need to be ruled out before a firm diagnosis of schizoaffective disorder can be made.

An initial assessment includes a comprehensive history and physical examination by a physician. Although there are no biological tests which confirm schizoaffective disorder, tests are carried out to exclude medical illnesses which rarely may be associated with psychotic symptoms. These include blood tests measuring TSH to exclude hypo- or hyperthyroidism, basic electrolytes and serum calcium to rule out a metabolic disturbance, full blood count including ESR to rule out a systemic infection or chronic disease, and serology to exclude syphilis or HIV infection; two commonly ordered investigations are EEG to exclude epilepsy, and a CT scan of the head to exclude brain lesions. It is important to rule out a delirium which can be distinguished by visual hallucinations, acute onset and fluctuating level of consciousness and indicates an underlying medical illness.

Investigations are not generally repeated for relapse unless there is a specific medical indication. These may include serum BSL if olanzapine has previously been prescribed, thyroid function if lithium has previously been taken to rule out hypothyroidism, liver function tests if chlorpromazine has been prescribed, and CPK levels to exclude neuroleptic malignant syndrome. Assessment and treatment are usually done on an outpatient basis; admission to an inpatient facility is considered if there is a risk to self or others.

The most widely-used criteria for diagnosing schizoaffective disorder are from the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, the current version being DSM-IV-TR:

DSM-IV-TR criteria[]

The following are the revised criteria for a diagnosis of schizoaffective disorder from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR):

A. Two (or more) of the following symptoms are present for the majority of a one-month period (or a shorter period of time if symptoms got better with treatment):

  • delusions
  • hallucinations
  • disorganized speech (e.g., frequent derailment or incoherence) which is a manifestation of formal thought disorder
  • grossly disorganized behavior (e.g. dressing inappropriately, crying frequently) or catatonic behavior
  • negative symptoms—e.g., affective flattening (lack or decline in emotional response), alogia (lack or decline in speech), avolition (lack or decline in motivation), anhedonia (lack or decline in ability to experience pleasure), social withdrawal (sometimes called social anhedonia). It should be noted that negative symptoms are different from symptoms of depression.
If the delusions are judged to be bizarre, or hallucinations consist of hearing one voice participating in a running commentary of the individual's actions or of hearing two or more voices conversing with each other, only that symptom is required to meet criterion A above. The speech disorganization criterion is only met if it is severe enough to substantially impair communication.

AND at some time during the illness there is either one, two or all three of the following:

B. During the same period of illness, there have been delusions or hallucinations for at least two weeks in the absence of prominent mood symptoms.

C. Symptoms that meet criteria for a mood episode are present for a substantial portion of the total duration of the active and residual periods of the illness.

D. The disturbance is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition.

Subtypes[]

Two subtypes of schizoaffective disorder exist and may be noted in a diagnosis based on the mood component of the disorder:

Bipolar type[]

if the disturbance includes

Major depressive episodes usually, but not always, also occur in the bipolar subtype, however they are not required for DSM IV diagnosis.

Depressive type[]

The depressive type is noted when the disturbance includes major depressive episodes exclusively.

This subtype applies if major depressive episodes only (and no manic or mixed episodes) are part of the presentation.

Controversies and research directions[]

Citing poor interrater reliability, some psychiatrists have totally contested the concept of schizoaffective disorder as a separate entity.[9][10] The categorical distinction between mood disorders and schizophrenia, known as the Kraepelinian dichotomy, has also been challenged by data from genetic epidemiology.[11] Consequently, some researchers have disputed that the term "schizoaffective disorder" refers to a well defined condition, and have recommended that the term be removed from or amended in future diagnostic manuals.[12] In April 2009, the DSM-V Psychotic Disorders Work Group headed by psychiatrist William T. Carpenter of the University of Maryland, College Park School of Medicine, reported that they will be "developing new criteria for schizoaffective disorder to improve reliability and face validity," and that they will be "determining whether the dimensional assessment of mood will justify a recommendation to drop schizoaffective disorder as a diagnostic category."[7] Speaking at the May 2009 annual conference of the American Psychiatric Association, Carpenter said, "We had hoped to get rid of schizoaffective [disorder] as a diagnostic category because we don't think it's valid and we don't think it's reliable. On the other hand, we think it's absolutely indispensable to clinical practice."[13]

Etiology and pathogenesis[]

Although the causes of schizoaffective disorder are unknown, it is suspected that this diagnosis represents a heterogeneous group of individuals, some with aberrant forms of schizophrenia and some with very serious forms of mood disorders. There is little evidence that schizoaffective disorder is a distinct variety of psychotic illness. Consequently, the disorder appears to be comorbid or (co-occurring) schizophrenia and mood disorder. Schizoaffective disorder thus appears to exist on a continuum in-between schizophrenia and severe bipolar disorder and severe recurrent unipolar depression. It follows then that the etiology is probably more similar to that of schizophrenia in some cases and more similar to severe mood disorders in other cases.

Many different genes may be contributing to the genetic risk of acquiring this illness. In addition, many different biological and environmental factors are believed to interact with the person's genes in ways which can increase or decrease the person's risk for developing schizoaffective disorder. Schizophrenia spectrum disorders (of which schizoaffective disorder is a part) have been marginally linked to advanced paternal age at the time of conception, a common cause of mutations.[14]

The physiology of patients diagnosed with schizoaffective disorder appears to be similar but not identical to that of those diagnosed with schizophrenia and severe bipolar disorder.[15]

Drug abuse[]

See also: Dual diagnosis

A clear causal connection between drug use and psychotic spectrum disorders, including schizoaffective disorder, has been difficult to prove. The two most often used explanations for this are "substance use causes schizoaffective disorder" and "substance use is a consequence of schizoaffective disorder", and they both may be correct.[16] In the case of marijuana or cannabis, however, evidence is mounting that it can play a role in the development and morbidity of psychotic disorders, including schizoaffective disorder.[17][18] For example, a 2007 meta-analysis showed that cannabis use is statistically associated with a dose-dependent increase in risk of development of psychotic disorders, including schizoaffective disorder.[17] Moreover, a 2005 meta-analysis found that cannabis use is a significant independent risk factor for developing psychotic symptoms and psychosis.[19] A 2009 Yale study stated that it is clear

"that in individuals with an established psychotic disorder, cannabinoids can exacerbate symptoms, trigger relapse, and have negative consequences on the course of the illness."[20]

On the other hand, a meta-analysis published in 2008 concluded that "Confidence that most associations reported were specifically due to cannabis is low. Despite clinical opinion, it remains important to establish whether cannabis is harmful, what outcomes are particularly susceptible, and how such effects are mediated."[21]

There is little evidence to suggest that other drugs including alcohol cause schizoaffective disorder, or that psychotic individuals choose specific drugs to self-medicate; there is some support for the theory that they use drugs to cope with unpleasant states such as depression, anxiety, boredom and loneliness.[22] However, regarding psychosis itself, it is well understood that methamphetamine and cocaine use can result in methamphetamine or cocaine induced psychosis which presents very similar symptomatology and may persist even when users remain abstinent.[23]

Epidemiology[]

Estimates of the prevalence of schizoaffective disorder vary widely, but schizoaffective manic patients appear to comprise 3-5% of psychiatric admissions to typical clinical centers. At one point it was widely believed that schizoaffective disorder was associated with increased risk of mood disorders in relatives. This may have been because of the number of patients with psychotic mood disorders who were included in schizoaffective study populations.

The current diagnostic criteria define a group of individuals with a mixed genetic picture. They are more likely to have schizophrenic relatives than individuals with mood disorders but more likely to have relatives with mood disorders than individuals with schizophrenia.

Treatment[]

Treatment for schizoaffective disorder consists of a combination of medicine, psychotherapy and psychosocial rehabilitation focused on recovery. Not all treatment services focus on recovery, however, so a recovery-oriented program may need to be sought out.

A licensed psychiatrist will prescribe (usually combinations of) medicine for the individual. Each person responds differently to medication. Common medicines used to treat schizoaffective disorder are listed below.

For psychotic symptoms, preferably one, but sometimes two neuroleptic medications are prescribed. Examples of neuroleptic medications include the following:

For manic symptoms, mood stabilizer medications may be prescribed along with a neuroleptic. Examples are:

For depression, antidepressant medications may be prescribed along with a neuroleptic. Examples are:

  • SSRI antidepressants (includes Prozac and Zoloft among others)
  • Lamictal (a mood stabilizer with antidepressant properties)

In schizoaffective individuals with manic symptoms, combining lithium, carbamazepine, or valproate with a neuroleptic has been shown to be superior to neuroleptics alone. Lithium-neuroleptic combinations, however, may produce severe extrapyramidal reactions or confusion in some patients.

When lithium is not effective or well tolerated in manic individuals with schizoaffective disorder, Tegretol or Depakote are frequently used. Granulocytopenia can occur during the first few weeks of carbamazepine treatment, and neuroleptic blood levels may be decreased substantially due to hepatic enzyme induction. Valproate can, in rare cases, cause liver toxicity and platelet dysfunction. Calcium channel blockers such as verapamil may also be an effective treatment for manic symptoms but are seldom prescribed for that purpose. The degree of benefit for an individual should be considered carefully, as each of these medications carries its own risks.

Benzodiazepines such as Ativan and Klonopin are effective adjunctive treatment agents for acute manic symptoms, but long-term use may result in dependency.

In schizoaffective individuals with depressive symptoms, an antidepressant (for example, Prozac or other SSRIs) may be prescribed with a neuroleptic. The SNRI antidepressants and Wellbutrin tend not to be prescribed in schizoaffective disorder because they may cause mixed episode symptoms and induce psychosis, respectively.

The anticonvulsant Lamictal is gaining prominence in treating depressed schizoaffective individuals because antidepressants appear to increase the risk of mood cycling in some individuals, which is a safety concern.

Often a sleeping pill will be prescribed initially to allow the individual rest from his or her anxiety, delusions or hallucinations. Long-term use of sleeping medications can, however, cause dependence and can also cause delusions and hallucinations thereby exacerbating psychosis.

Nutritional supplements and lifestyle changes are both being studied to augment existing treatments as well. Frequently co-occurring conditions such as mitochondrial dysfunctions, adrenal fatigue, sleep disorders, and diabetes are the targets of nutritional and lifestyle changes. Omega-3 fatty acid supplementation is used as a nutritional aid for many mental disorders including schizoaffective disorder. Some depressed schizoaffective individuals use 5-HTP, an amino acid and precursor to serotonin, in place of SSRI antidepressants to avoid associated side effects. Other supplements with antidepressant properties, St John's Wort and SAM-e, however, may cause adverse reactions of mixed-state symptoms or psychosis in depressed schizoaffective individuals.

Prognosis[]

People with schizoaffective disorder generally have a better outlook than those with schizophrenia, and about the same or worse outlook (depressive subtype having the least favorable outlook) as those with bipolar disorder. It is important to note that individual outcomes may be more favorable than those cited above since these prognoses are based on statistical averages of large groups of patients.

As with any chronic illness, compliance with medication is important, especially since more than one medication is often prescribed. Psychiatric rehabilitation plays an important part in maximizing the individual's chances at recovery, which may result in a better prognosis.

Complications[]

Complications are similar to those for schizophrenia and major mood disorders. These include:

  • Problems following medical treatment and therapy
  • Use of unsanctioned drugs in an attempt to self-medicate
  • Short-term side effects and problems arising from long-term use of prescribed medications, including drug interactions.
  • Problems resulting from manic behavior (for example, spending sprees, sexual indiscretion)
  • Suicidal behavior due to depressive or psychotic symptoms

History[]

The term schizoaffective psychosis was introduced by the American psychiatrist John Kasanin in 1933[26] to describe an episodic psychotic illness with predominant affective symptoms, that was thought at the time to be a good-prognosis schizophrenia.[27] Kasanin's concept of the illness was influenced by the psychoanalytic teachings of Adolf Meyer and Kasanin postulated that schizoaffective psychosis was caused by "emotional conflicts" of a "mainly sexual nature" and that psychoanalysis "would help prevent the recurrence of such attacks."[28] He based his description on a case study of nine individuals.[28]

Other psychiatrists, before and after Kasanin, have made scientific observations of schizoaffective disorder based on assumptions of a biological and genetic etiology of the illness. In 1863, German psychiatrist Karl Kahlbaum (1828-1899) described schizoaffective disorders as a separate group in his vesania typica circularis.[29] Kahlbaum distinguished between cross-sectional and longitudinal observations. (Cross-sectional refers to observation of a single, specific episode of the illness; for example, one episode of psychotic depression, while longitudinal refers to long-term observation of many distinct episodes [similar or different] often occurring over the span of years.) In 1920, psychiatrist Emil Kraepelin (1856-1926), the founder of contemporary scientific psychiatry, observed a "great number" of cases that had characteristics of both groups of psychoses that he originally posited were two distinct and separate illnesses, dementia praecox (now called schizophrenia) and manic depressive insanity (now called bipolar disorders and recurrent depression).[28] Kraeplin acknowledged that "there are many overlaps in this area," that is, the area between schizophrenia and severe mood disorders.[30] In 1959, psychiatrist Kurt Schneider (1887–1967) can be said to have been the first to begin to conceptualize the different forms that schizoaffective disorders can take since he observed "concurrent and sequential types."[28] (The concurrent type of illness he referred to is a longitudinal course of illness with episodes of mood disorder and psychosis occurring predominantly at the same time; while his sequential type refers to a longitudinal course predominantly marked by alternating mood and psychotic episodes.)[29] Schneider described schizoaffective disorders as "cases in-between" the traditional Kraepelinian dichotomy of schizophrenia and mood disorders.[29]

The historical phenomenological observation that schizoaffective disorder is an overlap of schizophrenia and severe mood disorders has more recently been assumed to be explained by genes for both illnesses being present in individuals with schizoaffective disorder. But recent research shows that schizophrenia and severe mood disorders appear to share common genes and polygenic variations also.[31][32][33][34][35]

Schizoaffective disorder was included as a subtype of schizophrenia in DSM I and DSM II, though research showed a schizophrenic cluster of symptoms in individuals with a family history of mood disorders whose illness course, other symptoms and treatment outcome were otherwise more akin to bipolar disorder than to schizophrenia. DSM III placed schizoaffective disorder in psychotic disorders Not Otherwise Specified before being formally recognized in DSM III-R.[36] DSM III-R included its own diagnostic criteria as well as the subtypes, bipolar and depressive.[36] In DSM IV, published in 1994, schizoaffective disorders belonged to the category "other psychotic disorders" and included almost the same criteria and the same subtypes of illness as DSM III-R, with the addition of mixed bipolar symptomatology.[37]

See also[]


References[]

  1. http://www.who.int/classifications/apps/icd/icd10online/
  2. Template:DorlandsDict
  3. Kaplan & Saddock. p.501-502
  4. Kaplan & Saddock. p.502
  5. Becker T, Kilian R (2006). Psychiatric services for people with severe mental illness across western Europe: what can be generalized from current knowledge about differences in provision, costs and outcomes of mental health care?. Acta Psychiatr Scand Suppl (429): 9–16.
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  7. 7.0 7.1 Report of the DSM-V Psychotic Disorders Workgroup, http://www.psych.org/MainMenu/Research/DSMIV/DSMV/DSMRevisionActivities/DSM-V-Work-Group-Reports/Psychotic-Disorders-Work-Group-Report.aspx, retrieved on 2009-08-02 
  8. DSM on Track for 2012, But Difficult Decisions Lie Ahead. URL accessed on 2009-08-03.
  9. Lake CR, Hurwitz N (July 2007). Schizoaffective disorder merges schizophrenia and bipolar disorders as one disease--there is no schizoaffective disorder. Curr Opin Psychiatry 20 (4): 365–79.
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  12. Malhi GS, Green M, Fagiolini A, Peselow ED, Kumari V (February 2008). Schizoaffective disorder: diagnostic issues and future recommendations. Bipolar Disorders 10 (1 Pt 2): 215–30.
  13. DSM on Track for 2012, But Difficult Decisions Lie Ahead. URL accessed on 2009-08-03.
  14. Brown AS, Schaefer CA, Wyatt RJ, et al. (September 2002). Paternal age and risk of schizophrenia in adult offspring. The American Journal of Psychiatry 159 (9): 1528–33.
  15. Martin LF, Hall MH, Ross RG, Zerbe G, Freedman R, Olincy A (December 2007). Physiology of schizophrenia, bipolar disorder, and schizoaffective disorder. The American Journal of Psychiatry 164 (12): 1900–6.
  16. Ferdinand RF, Sondeijker F, van der Ende J, Selten JP, Huizink A, Verhulst FC (2005). Cannabis use predicts future psychotic symptoms, and vice versa. Addiction 100 (5): 612–8.
  17. 17.0 17.1 Moore TH, Zammit S, Lingford-Hughes A, et al. (March 2005). Cannabis use and risk of psychotic or affective mental health outcomes: a systematic review. Lancet 370 (9584): 187–94.
  18. Semple DM, McIntosh AM, Lawrie SM (March 2005). Cannabis as a risk factor for psychosis: systematic review. J. Psychopharmacol. (Oxford) 19 (2): 187–94.
  19. Semple DM, McIntosh AM, Lawrie SM (March 2005). Cannabis as a risk factor for psychosis: systematic review. J. Psychopharmacol. (Oxford) 19 (2): 187–94.
  20. D'Souza DC, Sewell RA, Ranganathan M (July 2009). Cannabis and psychosis/schizophrenia: human studies. Eur Arch Psychiatry Clin Neurosci.
  21. Zammit S, Moore TH, Lingford-Hughes A, Barnes TR, Jones PB, Burke M, Lewis G (November 2008). Effects of cannabis use on outcomes of psychotic disorders: systematic review. Br J. Psychiatry 193 (5): 357–63.
  22. Gregg L, Barrowclough C, Haddock G (May 2007). Reasons for increased substance use in psychosis. Clinical Psychology Review 27 (4): 494–510.
  23. Mahoney JJ, Kalechstein AD, De La Garza R, Newton TF (2008). Presence and persistence of psychotic symptoms in cocaine- versus methamphetamine-dependent participants. The American Journal on Addictions 17 (2): 83–98.
  24. 24.0 24.1 Keks NA, Ingham M, Khan A, Karcher K (August 2007). Long-acting injectable risperidone v. olanzapine tablets for schizophrenia or schizoaffective disorder. Randomised, controlled, open-label study. The British Journal of Psychiatry 191: 131–9.
  25. Flynn J, Grieger TA, Benedek DM (January 2002). Pharmacologic treatment of hospitalized patients with schizoaffective disorder. Psychiatric Services (Washington, D.C.) 53 (1): 94–6.
  26. Lake CR, Hurwitz N (August 2006). Schizoaffective disorders are psychotic mood disorders; there are no schizoaffective disorders. Psychiatry Research 143 (2-3): 255–87.
  27. Goodwin & Jamison. p102
  28. 28.0 28.1 28.2 28.3 Goodwin & Marneros. p190
  29. 29.0 29.1 29.2 Goodwin & Marneros. p189
  30. Marneros & Akiskal. p3-4
  31. Van Snellenberg JX, de Candia T (July 2009). Meta-analytic evidence for familial coaggregation of schizophrenia and bipolar disorder. Arch. Gen. Psychiatry 66 (7): 748–55.
  32. (June 2009) Schizophrenia and bipolar disorder may share genetic origins. Harv Ment Health Lett 25 (12): 7.
  33. Purcell SM, Wray NR, Stone JL, et al. (July 2009). Common polygenic variation contributes to risk of schizophrenia and bipolar disorder. Nature.
  34. Potash JB, Bienvenu OJ (June 2009). Neuropsychiatric disorders: Shared genetics of bipolar disorder and schizophrenia. Nat Rev Neurol 5 (6): 299–300.
  35. Craddock N, Owen MJ (May 2005). The beginning of the end for the Kraepelinian dichotomy. Br J Psychiatry 186: 364–6.
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  37. Goodwin & Marneros. p192

Cited texts[]

  • Marneros A, Akiskal, HS (2007). The Overlap of Schizophrenic and Affective Spectra, New York: Cambridge University Press.
  • Goodwin FK, Jamison KR (2007). Manic-Depressive Illness: Bipolar Disorders and Recurrent Depression, 2nd Edition, New York: Oxford University Press.
  • Kaplan HI, Saddock VA (2007). Synopsis of Psychiatry, New York: Lippincott, Williams & Wilkins.
  • Murray WH (2006). Schizoaffective Disorders: New Research, New York: Nova Science Publishers, Inc.
  • Goodwin FK, Marneros, A (2005). Bipolar Disorders: Mixed States, Rapid Cycling and Atypical Forms, New York: Cambridge University Press.
  • Moore DP, Jefferson JW. Handbook of Medical Psychiatry. 2nd ed. St. Louis, Mo: Mosby; 2004:126-127.
  • Goetz, CG. Textbook of Clinical Neurology. 2nd ed. St. Louis, Mo: WB Saunders; 2003: 48.

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