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THE SIGNIFICANCE OF OBSESSIONS AND COMPULSIONS IN SCHIZOPHRENIA.
A LITERATURE REVIEW & CASE STUDY.
Iain W. McGowan (1), Julie McIlroy (2),
1.School of Nursing, University of Ulster, Northern Ireland
2.Dept of Psychiatry, Mater Hospital Trust, Belfast, Northern Ireland
Corresponding author: Iain W. McGowan, BSc (Hons), RMN, Lecturer in Nursing, School of Nursing, University of Ulster, Cromore Road, Coleraine, Northern Ireland, United Kingdom. IW.McGowan@ulster.ac.uk
The last five years has seen a profileration of interest in the co-morbid presence of schizophrenia and obsessive compulsive disorder. This paper reviews classic and contemporary literature in both fields as single entities and as a dual condition. The clinical significance of a dual diagnosis is explored. A case study is offered by way of example. The paper concludes that individuals with co-morbid OCD & schizophrenia have poorer clinical outcomes than their peers with a singular diagnosis
Key words: obsessive compulsive disorder, schizophrenia, dual diagnosis
Schizophrenia is a clinical syndrome of both extraordinary importance and extraordinary complexity (Andreasen and Carpenter, 1993). The term "schizophrenia" was introduced by the Swiss psychiatrist Eugen Bleuler (1911) who coined the term "the group of schizophrenia's" because 'the disconnection or splitting of psychic functions is an outstanding feature' of the presentation (Murray, 1997).
Bleulers' classification of 'schizophrenia' adopted a more cross- sectional approach than previous attempts at classification. In particular, he differed in his view of schizophrenia from Emile Kraepelin; the German psychiatrist widely regarded as being the originator of the concept of disease, which was neither melancholic nor manic. Kraepelin (1919) brought together hebephrenia, catatonia and paranoia into a single disease entity named dementia praecox. The characteristics of which included, hallucinations, delusions, a decreased attention to the world, lack of curiosity, thought disorder, lack of insight and judgement, and emotional blunting. He believed that the disease had its onset in early adult life (praecox) and led to an irreversible impairment of cognitive and behavioural function (dementia).
Bleuler (1911) concurred on many aspects of Kraepelins' (1919) writings, however he focussed on the symptomatology of the disease when attempting to classify. In essence he broadened the boundaries of Kraeplins concepts. Bleuler distinguished primary symptoms - thought disorder, ambivalence, affective blunting and autism- from secondary symptoms - hallucination and delusions- which, he argued, could appear in other illnesses.
Murray (1997) notes that his primary symptoms were so difficult to define that they allowed a great deal of subjective "latitude" on the clinicians' part. Similarly, the use of the term "autism" is a cause of confusion in some quarters. Bleuler (1911) used the term to describe the turning away from the external environment into a private world of fantasy (Wing, 1978), which resulted in "The reality of the autistic world [seeming] more valid than reality itself" (Bleuler, 1911). This differs from the common understanding of autism as a syndrome observed in small children that show disturbances of affect, as introduced by Kanner (1942). Nevertheless, Bleulers' understanding of schizophrenia was adopted in the United States of America as one diagnostic criterion. Conversely, Kraepelins' proposal featured predominantly in the development of the European diagnostic criteria for schizophrenia (Doherty, 1999).
The symptomatology of schizophrenia continues to receive much interest in clinical and psychiatric research fields. Schneider (1951) made, what is regarded as, the most influential attempt at a definition of schizophrenia. He proposed- using an atheoretical approach- that schizophrenia had "first rank" symptoms. These symptoms included hallucinations and thought interference and the use of such criteria resulted in an improved inter- rater reliability for the diagnosis of schizophrenia. As such, it was quickly adopted into European psychiatry (Doherty, 1999). A number of commentators have, however, raised concerns over the validity of the concept of schizophrenia as diagnosed using this criteria (Brockington, Kendell and Leff, 1978) and it is argued that the specified symptoms are both too narrow and insufficiently specific (Murray, 1997).
EPIDEMIOLOGY OF SCHIZOPHRENIA
Epidemiological studies of schizophrenia are hampered by a number of factors. Variable diagnostic definitions, difficulties in identification of all cases in a given population, and the ambiguity about the exact date of onset- the date when the illness first became apparent- have all plagued researcher investigation on the distribution of schizophrenia (Frangou and Murray, 2000). However it is generally accepted that schizophrenia occurs in all cultures and that the annual incidence of schizophrenia is between 0.02 and 0.04% (Jablenska, Sartorius and Ernberg, 1992) with a lifetime risk of developing schizophrenia of 1%.
The World Health Organisation, through the International Pilot Study of the Schizophrenia (Jablensky, Sartorius. Emberg et al 1992), attempted to establish the occurrence of schizophrenia across 10 countries of varied cultural and developmental standing. This study, essentially, concluded that schizophrenia could be reliably diagnosed across all cultures. However, dispute exists over the interpretation of their results in regard to the occurrence of schizophrenia.
Farangou and Murray (2000) contend that the findings are often misquoted as showing a similar episodic rate, when in fact the correct interpretation, according to them, is that the rate of schizophrenia defined by the broad criteria of DSM-III varied by a factor of four across cultures. The study, they argued, also lacked the statistical power to establish any cultural differences using the narrower ICD-9 criteria.
Gender and age differences also exist in the distribution of schizophrenia. Generally males develop schizophrenia five years earlier that females, with a peak incidence of onset of between 15 and 25 years of age, in comparison to 25 and 35 years in their female counterparts (Hafner, Maurer, Loffler et al, 1994)
A number of social factors have also shown to be present in the epidemiology of schizophrenia. In industrialised countries, there are more people with schizophrenia in the lower socio-economic classes (Freeman, 1994; Loffler and Haffner, 1999) and there are greater hospital admission rates for schizophrenia in urban areas in comparison to rural constituencies (Freeman, 1994; Loffler and Haffner, 1999). Within the urban areas they are higher in socially disadvantaged areas (Freeman, 1994; Loffler and Haffner, 1999).
THE CLINICAL PICTURE OF SCHIZOPHRENIA
The clinical presentation of schizophrenia varies both between individuals and within the same individual at different stages of the illness.
The IPSS (1992) identified a number of symptoms that frequently occurred in schizophrenia. The ten most common being (frequency (%) shown in brackets): Lack of insight (97); auditory hallucinations (74); ideas of reference (70); suspiciousness (66); flatness of affect (66); second person hallucinations (65); delusional mood (64); delusions of persecution (64); thought alienation (52); and thought broadcast (50). These symptoms tend to present in the acute phase of the illness. Chronicity in schizophrenia appears to be associated with negative symptoms- poverty of thought and speech; impaired volition; blunted affect; loss of interest and motivation and social withdrawal.
Social and cognitive deficits have also been noted in the premorbid and prodromal phases of schizophrenia. Jones, Rodgers, Murray et al (1994), in a prospective study of over 4500 people born in the UK on the same week in 1946 found significant differences (95% confidence level) in motor, linguistic and social dysfunction in children that later developed schizophrenia, in comparison with their peers that did not develop schizophrenia. Similarly increased deviance with age and cognitive deficits became progressively more marked in early adolescence.
The onset of the prodromal phase can be insidious with non- specific symptoms and delineating the premorbid personality and prodromal state can be difficult.
Often the prodromal phase involves a continued deterioration of functional capabilities accompanied by odd ideas, eccentric interests, changes in affect, unusual speech and bizarre perceptual experiences (Frangou and Murray 2000).
Schizophrenia has, historically, been regarded as having a 'course of illness' characterised by continual and marked decline in function. This however has not been borne out in recent research. In a five-year follow up of 49 first episode schizophrenics Shepard, Watt, Fallon et al (1989) reported four groups with differing courses and clinical outcome. 22% of the study population had a singular index episode with no evident functional impairment. The second group (35%) had several relapses but minimal or no impairment. Group 3 (8%) displayed impairment following the index episode with subsequent exacerbation and no return to normality. The final group (35%) had impairment increasing with subsequent frequent relapses and no return to pre- illness normality.
The clinical outcome of schizophrenia can best be considered along two major axis: the degree of symptomatic recovery and the level of social functioning (Farangou and Murray, 2000).
OBSESSIVE COMPULSIVE DISORDER
As with schizophrenia the concept and classification of OCD is obtuse and inconclusive. It is not a new phenomenon and descriptions of classic OCD can be traced back to the 16th century. Records of 17th century religious figures relating stories of OCD sufferers have been uncovered and OCD has featured in some classic works of literature.
MacBeth in Shakespeares' play of the same name, relates of his wife "It is an accustomed action with her, to seem thus washing her hands. I have known her continue with this a quarter of an hour", for instance.
There has been a renewed interest in the field of Obsessive Compulsive Disorder over the last fifteen years. This can partly be attributed to the finding of the Epidemiological Catchment Area Study that identified that OCD was around 40 times more prevalent than originally thought.
The result being an increased interest on all aspects of OCD including childhood OCD, simple, or classic OCD and comorbid OCD.
There has also been an increase in studies in the fields of disease entities in the Obsessive Compulsive Spectrum of disorders. Hollander (1993) listed these disorders as body dismorphic disorder, hypocondriasis, depersonalization disorder, anorexia nervosa, bulimia nervosa , Trichotillomnia (pathological hair pulling), pathological gambling, paraphilias, multiple tics syndrome, onchyphagia, delusional disorders, Sydenhams chorea, Parkinsons disease, epilepsy and autism. He then expands the list further by including developmental disorders such as Aspergers syndrome.
The completeness of this all encompassing attempt at classifying the disorder to include such a vast array of behaviours and associated cognitive and affective components has been challenged by Rasmussen (1994).
Rasmussen argued that classification the disorder should be reduced to a smaller list of disorders related by either a feature of harm avoidance or incompleteness. He did concur with Hollander that there was a widespread overlap of OCD and a broad range of other conditions.
Obsessive compulsive disorder is characterised "recurrent obsession thoughts or compulsive acts" (WHO 1992). Obsessional thoughts are ideas, images or impulses that enter the patients' mind repeatedly in a stereotyped form. They are invariably unpleasant and distressing and the patient often tries, unsuccessfully, to resist them.
Compulsive acts or rituals are those are repeated again and again in a stereo typed manner. Similar to obsessions the acts are distressing. They are often pointless, serving no useful purpose except to prevent an unlikely event- harm to themselves or others- by their repetition. The patient usually recognises their behaviour as futile, however attempts to resist the compulsive behaviour results in an increased and at times unbearable, anxiety.
Given the vast range of associated disorders it would be assumed that diagnosising OCD would be difficult. However, in practice it has been shown to be relatively straightforward. The main difference in presentation of OCD and other associated illnesses is that the OCD sufferers attempt to hide the symptomatology. This is particularly so where a comorbid psychiatric condition is present.
THE EPIDEMIOLOGY OF OBSESSIVE COMPULSIVE DISORDER
Until 1984, the most widely quoted figure in relation to the prevalence of OCD in the general population was 0.05% (Montgomery and Zohar, 1999). However, these studies were based on a population of those with severe OCD, so much so that they required hospitalisation. In effect biasing the research toward a hospital population, rather than the general population.
The Epidemiological Catchment Area Survey (ECA) (Robins, Helzer and Weissman, 1984) found a general population prevalence some 40 times greater than previously thought at 2%. This is second only to a major depressive episode and twice the rate of schizophrenia. This study screened the general population for psychiatric disorder (n= 18, 000) with a view to establishing the lifetime and 6 month prevalence of psychiatric disorder in the USA.
Weissman, Bland and Canino (1994) carried out a crossnational epidemiological study examining the prevalence of OCD across national and cultural boundaries. Using standardised methods and diagnostic criteria they found a prevalence rate of around 2% in all locations (the USA, Canada, Puerto Rico, Germany, Korea and New Zealand) with the exception of Taiwan. The Taiwanese study revealed a rate of 0.7%, however it is argued that this reflects the low rate of psychiatric morbidity in Taiwan (Montgomery and Zohar 2000).
OCD has an early age of onset with a mean age of 19- 20 years., although retrospective studies have indicated that between 30% and 50% of adults' report that their symptoms started in childhood or adolescence (Montgomery and Zohar 2000).
THE CLINICAL PICTURE OF OBSESSIVE COMPULSIVE DISORDER
Rasmussen and Tsuang (1986), in a study of 250 people admitted to hospital for treatment of OCD found the following obsessions and compulsions (% in brackets) prevalent in their group: fear of contamination (45%), pathological doubt (42%), somatic (36%), need for symmetry (31%), aggressive impulse (26%), sexual impulse (26%) and others (13%). Interestingly they relate that 60% of the population displayed two or more obsessions. Compulsions included: checking (60%), washing (50%), counting (36%), need to ask or confess (31%), symmetry/ precision (28%), hoarding (18%), and, again a substantial proportion (48%) displayed more than one compulsion.
OBSESSIONS AND COMPULSIONS IN SCHIZOPHRENIA.
The last five years, or so, has seen a renewed interest in the development of obsessive- compulsive disorder in the schizophrenic population. This, it is argued, is partly due to the publication of a number of case studies detailing apparent psycho- pharmacological induced obsessive- compulsive symptoms in-patients treated with atypical antipsychotics.
Contemporary studies- those recent studies using standardised classification methods- appear to have concentrated on measuring the prevalence, incidence, demography and clinical correlates of the overlap.
Eisen at al (1997) in what is, they contend, the primary study to utilise standardised rating scales and diagnostic criteria studied, a cohort of 77 patients drawn from two mental health out- patient clinics in the USA. Using a structured interview design the results demonstrated that 7.8% of the 77 patients meeting DSM- III- R criteria for both obsessive compulsive disorder and schizophrenia spectrum disorders. They argue that by using previously validated rating scales- the Structured Clinical Interview for DSM-III-R - Patients Edition and the Yale Brown Obsessive Compulsive Scale (Goodman 1989) - as well as diagnostic criteria that the results will hold more sway than historical studies. Despite the relatively small sample size Eisen et al conclude that a "substantial" number of patients with schizophrenia also have co-morbid OCD. Having established two separate groups from their original cohort they investigated demographic and psychiatric differences between them. They found that there were no apparent differences in variables such as gender, work status, number of admissions or age of onset of schizophrenia between the groups with and without OCD. A statistically significant difference (p=0.01, Fishers exact test; two tailed) was noted between the clinical diagnosis of the group with OCD; 20% those with a schizoaffective disorder had OCD compared with only 2% with simple schizophrenia. The significance of this, however, was not commented upon.
Berman, Merson, Viegner et al (1998) carried out structured interviews with the therapists of 102 people with chronic schizophrenia (DSM-III-R) who attend a community mental health facility in Brooklyn, New York.. They discovered a 25% incidence rate of OCD in their research sample. The demographics in this study point to a younger age of onset, length of time hospitalised and level of function as statistically significant in the study population, as markers for developing OCD. Again, the lack of standardised criteria may effect the generalizability of their results.
Other studies, replicating the design of Eisen et al, identified prevalence rates of 23.5% (Poyurovsky, Hramenkov, Isakov, et al., 2001) in chronic schizophrenics and 13% (Rabe- Jablonska, 2001) in chronic adolescent schizophrenics.
Drawing their research sample from 68 "hospitalized chronic schizophrenics" Poyurovsky et al (2001) report that those patients with obsessions had were significantly impaired in social functioning, using the Social Behaviour Schedule.
No significant differences were found in a variety of clinical variables including positive and negative symptoms, abnormal involuntary movements and akathesia between the obsessives and non- obsessives.
Rabe- Jablonska (2001) focussed on the role of anti- psychotic medication in inducing OCD in a schizophrenic population. Sampling 200 Polish adolescents (15-19 years of age) with schizophrenia diagnosed no less that 6 months prior to the study. Examination of the findings of the study suggests that patients previously treated with classical neuroleptic medication, developed OCD on changing to atypical medication. It is suggested that the medication may therefore induce OCD symptoms, in essence causing an iatrogenic effect. The significance of this is not addressed in the abstract.
In a study of 50 patients admitted to hospital with a first episode of psychosis, Poyurovsky at el. (1998) found a diagnosis of OCD- using DSM- IV criteria- in 14%. Using the same methodology as Eisen et al, they managed to negate the possible negative effects of antipsychotic medication by surveying a convenience sample that were drug naïve or had less than twelve weeks exposure to neuroleptics. The results mimic those found by Eisens' group, in terms of demographics. They also found less severity of formal thought disorder and blunting in the group with OCD alluding to a possible protective effect of the OCD on clinical outcome.
The prevalence rate in this study is consistent with that of Berman et al (1998), double Eisens' results and around half of the other studies. The clinical significance of these findings is unclear from the papers reviewed.
The clinical significance of OCD in schizophrenia.
The clinical significance of OCD in schizophrenia can be viewed in two ways: either as a precursor for development of schizophrenia; or as an indicator of clinical outcome. Both of which are reviewed below.
OCD as a precursor to schizophrenia.
Rosen (1957) noted that it was well known that obsessive- compulsive symptoms occur in the prodromal phase of schizophrenia. He reflected on the notion that obsessions can develop into delusional thinking and a full- blown schizophrenic episode. Historically the debate may have been clouded by the absence of a standard diagnostic criteria and Bleuler (1911) argued that some patients with chronic obsessional symptoms were, in fact, schizophrenic. Brunswick (1928) relates that she successfully treated for a paranoid state a patient treated for years by Freud for obsessional symptoms. As Rosen notes, Binder (1944; 1945) also argued that obsessions and compulsions could lead to schizophrenia. He contended that the development into schizophrenia could lead to criminal behaviour. Rosen, himself, found all thirty patients in his study, drawn from 848 schizophrenics treated at the Bethlem Royal and Maudsley Hospitals, who displayed OCD had reported obsessive- compulsive symptoms prior to the onset of schizophrenia (Rosen, 1957).
In the only recent research paper apparent in addressing this issue, Rabe- Jablonska (2001) suggests a minimal risk of developing schizophrenia as a result of presenting OCD symptoms. He found that 2% of chronic adolescent schizophrenics had pre- existing OCD before the onset of schizophrenia.
The effect of OCD on the clinical outcome of schizophrenia.
The effect that OCD has on the clinical outcome of schizophrenia has not yet been fully explored. Patients displaying co- morbid OCD and schizophrenia have been shown to have significantly higher positive and emotional discomfort symptoms, poorer executive brain function (Lysaker, Marks, Picone, et al., 2000), reduced capacity for global, social and economic functioning (Fenton and McGlashan, 1986) (Tibbo, Kroetsch, Chue, et al., 2000); (Berman, Merson, Viegner, et al., 1998)), significantly increased negative symptoms, and an increased trend toward Parkinsonian symptoms (Tibbo, Kroetsch, Chue, et al., 2000); (Poyurosky, Bergman, Shoshani, et al., 1998) than their counterparts without OCD.
Two recent studies investigating the significance of obsessions and compulsions in schizophrenia found no statistically significant differences between symptom presentation, obsessive-compulsive scores, social functioning and abnormal involuntary movements (Poyurovsky et al 2001; Rabe- Jablonska 2001).
In short all studies to date appear to have provided evidence for the existence of OCD in schizophrenia although their significance remains elusive. To conclude co-morbid schizophrenia and OCD appears to have a negative impact on the individual sufferer. More research is needed to identify those at risk of developing the illnesses and to establish treatment protocols.
Peter, a 32-year-old gentleman, with a history of schizophrenia dating back over 10 years has recently been diagnosed as suffering from co-morbid Obsessive Compulsive Disorder. Peter began suffering psychotic type symptoms when he was 16 years old, but a formal diagnosis was not formulated until 7 years later, following several admissions to psychiatric hospitals- A formal diagnosis was not formulated until a period of time following Peter s initial contact with mental health services, in order to fully assess his menial state and symptoms experienced. Consequently, a diagnosis of paranoid schizophrenia was made in 1992. Peter experiences a number of symptoms associated with schizophrenia including auditory hallucinations, suspsciousness, and delusional mood associated with impaired volition, blunted affect and social withdrawal Peter describes his symptoms, particularly auditory hallucinations, as very distressing but relatively well controlled at present due to his prescribed medication. Peter shows considerable insight into the necessity with which he must adhere to has medication regime and rarely, if ever omits his medication. Following Peter's diagnosis he was prescribed a typical older style anti-psychotic, in varying doses for approximately 4 years, in association with an antidepressant. During this time Peter was admitted to psychiatric unit for assessment and treatment as a result of an exacerbation of his symptoms. The assessment period resulted in a change of treatment from the older anti-psychotic to a newer atypical style medication, on which he remained for a short time. In the late 1990's, following a severe relapse Peter was admitted to hospital and again reassessed, during which time his medication was altered. It was felt appropriate to prescribe a different anti- psychotic, on which he presently remains, together with various other medications.
From Peter's medical notes it was ascertained that he was diagnosed as suffering from Obsessive Compulsive Disorder in 1999 and during interview he described the symptoms he experienced as a result of this condition- Peter reports that the symptoms began around 3 years ago, although he could not be of an exact time frame, as he often gets confused when thinking of events, but describes how this condition has become increasingly worse, over the past year. Peter describes his symptoms to include checking, collecting objects from the street and most notably, counting. When living independently in the community Peter describes how he felt the need to repeatedly check that taps were turned off, doors and windows locked and secured and felt compelled to collect pieces of glass, bottle tops and other objects from the street, not knowing why he felt thee necessity to carry through these actions. Considering Peter's experiences of schizophrenia, his behaviour may be rationalised as that of someone aiming to protect themselves and their surroundings. Presently Peter is not living in the community, and has not been for several months, and is not experiencing the need to constantly check his security. Peter's main obsessional thought at present is associated with counting, and he verbalises the distress and concern this causes him. Peter is constantly aware of his need to count and especially "round up'" numbers to a certain figure. Peter discusses how his compulsion to count is triggered by various factors, such as the bleep from the washing machine to indicate it finishing; in this instance he feels he must round up the number from 4 bleeps to 5 by clicking his fingers. He also describes counting panels in ceilings and walls, but that he can be distracted from these thoughts by listening to music and concentrating on the music.
As a gentleman Peter is pleasant on approach and very willing to co-operate but becomes less pleasant when describing the effects of his obsessional thoughts, showing signs of anxiety and slight agitation. Peter recognises that his actions are futile and finds his compulsion to carry out these acts distressing but less so than the anxiety caused when he attempts to resist them. Presently Peter is coping with his co-morbid conditions, and at times finds it extremely difficult, but is willing to accept help in the form of Mental Health Support and guidance from professionals.
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